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Advance warning: I'm only an anthropology undergrad. I am very near to graduating, though, and looking into advanced degrees and a research career in gender and sexuality. This is my passion.

Looking at the promiscuous (according to Westerners) sexual behavior of egalitarian foragers (which humans were for the majority of our existence), and looking at the behavior of the Bonobo, our nearest living relative, and finally looking at the way that both of us use oxytocin to ease social bonding...

It seems pretty obvious. So that we can have sex whenever we want. It's a good strategy. Sex is an enjoyable act that nearly all humans love. It's relaxing, it's great for forming emotional bonds (note: not necessarily romantic bonds, as most today would know them), and it produces children. It keeps things running smoothly, which is important in an egalitarian society.

Infanticide was pretty common in prehistory. The sheer number of infant remains seriously skews life expectancy data, actually, leading to the myth that prehistoric people didn't live past 30. It's not that these people were horrible, just that they couldn't feed every child they brought into the world. Foraging keeps a pretty hard limit on population growth. They didn't have the means to safely conduct abortions, and many, if not most people didn't grasp the connection between sex and pregnancy. This is understandable for people who are having a lot of sex with multiple people in their <120-ish person band; pregnancy would seem like something that just starts happening once a woman reaches a certain age.

But despite all the infanticide—or perhaps because of it—a child which is chosen to be kept has a very good chance for survival. With no parternity certainty, promiscuous foragers tend to care for all of the band's children; not just their own. They grow up with a great deal of social support. In a group dynamic like this, promiscuity is an advantageous behavior.

There's a great book on human sexuality that I would recommend reading. Not buying, unless you really dig it (I did). Just check it out at the library or flip through it over coffee at Barnes and Noble or something. Or, hell, pirate an ebook if you can find one. It's called Sex At Dawn, and I found it to be a pretty solid interdisciplinary analysis of the research thus far. It's written to the layman—in that it avoids jargon and keeps a playful tone—but it's quite informative, particularly if you follow along with the end notes. They go into much greater detail there. Also of value are the references. I've only just begun going through those.

These rules arise from the solutions of the Schroedinger equation for a central potential.

The nucleus of the atom provides an attractive potential in which electrons can be bound. As the mass of even a single proton is roughly 1800 times that of an electron the nuclei can be treated as stationary charged points that the electrons orbit around. The resulting coulomb potential is a central potential, that is it only depends on the distance from the nucleus, not the direction from the nucleus.

See http://en.wikipedia.org/wiki/Hydrogen-like_atom for some of the derivation, but if you don't know differential equations and quantum mechanics at least at an introductory level it will not make much sense. Griffiths does a good introductory quantum text if you are interested in reading more. Link on amazon.com.

As it is a bound system in quantum mechanics only certain values of energy and momentum can be taken. The allowed energy levels are denoted by the quantum number n. The energy of a level is given is proportional to -1/n^2 in the simple hydrogenic atom model where the energy is negative that gives a bound state, and energies above zero are unbound, so as the energy increase the electrons in the higher n orbitals require less energy to become unbound.

For a given n there are certain values of angular momentum that can occur, and these are designated l and range from 0 to n. For a given l there are then the m_l magnetic quantum numbers ranging from +l to -l in integer steps. In the simple atom models the m_l do not effect the energy level.

Higher angular momentum of the electron implies a higher energy So 2s (n=1,l=0, m_l=0) has lower energy than 2p (n=2, l=1, m_l= 1,0,-1)

Each letter corresponds to an l value and arose from the way the lines looked in spectrographs and the meaning of the letter abbreviation is pretty much ignored these days with the current understanding of the the underlying quantum numbers.

s-> l=0 (sharp lines)

p->l=1 (principle lines)

d->l=2 (diffuse lines)

f->l=3 (fundamental lines)

http://www.tutorvista.com/content/chemistry/chemistry-iii/atomic-structure/electronic-configuration.php

Shows some of the simpler rules for determining the order of filling of the orbitals based on the energy level of the combined n and l values.

Two show how oxygen needs an octet to be stable we can do:

Oxygen has 8 protons and will be neutral with 8 electrons.

2 go into the 1s orbital, and it it is designated 1s^2, the superscript giving the number of electrons present in the n=1 l=0 m_l=0 and m_s =+1/2,-1/2. m_s is the magnetic quantum number for the electrons own internal angular momentum which has s=1/2 so can take m_s=+1/2 or m_s=-1/2.

The next higher energy orbital (look at the squiggly line diagram giving the filling order for electrons into orbitals, this is essentially filling in order of lowest energy orbitals first) is the 2s and it can have two electrons like the 1s, so we write 2s^2 for the full orbital.

There are now 4 more electrons to take care of, and they can go into the 2p orbital and that can hold up to 6 electrons, but we only fill in 4 for 2p^4 .

We can fully write the electron configuration as 1s^2 2s^2 2p^4 . If the oxygen borrows two more electrons (say one each from two hydrogens) they can move into the remaining 2p orbitals that are not full.

In the n=2 orbitals that then gives a total of 8 electrons.

Going into the higher orbitals requires more energy than the lower orbitals so it would not be a stable ground state. To put it differently if two hydrogen atoms are going bond to an oxygen it needs to go into a lower energy state than the separate atoms. If a bound state does occur with the lower energy atoms this is then an excited state that will decay into the grounds state by emission of a photon (light).

I'm assuming you're looking for things geared toward a layman audience, and not textbooks. Here's a few of my personal favorites:

Sagan

Cosmos: You probably know what this is. If not, it is at once a history of science, an overview of the major paradigms of scientific investigation (with some considerable detail), and a discussion of the role of science in the development of human society and the role of humanity in the larger cosmos.

Pale Blue Dot: Similar themes, but with a more specifically astronomical focus.


Dawkins

The Greatest Show on Earth: Dawkins steers (mostly) clear of religious talk here, and sticks to what he really does best: lays out the ideas behind evolution in a manner that is easily digestible, but also highly detailed with a plethora of real-world evidence, and convincing to anyone with even a modicum of willingness to listen.


Hofstadter

Godel, Escher, Bach: An Eternal Golden Braid: It seems like I find myself recommending this book at least once a month, but it really does deserve it. It not only lays out an excruciatingly complex argument (Godel's Incompleteness Theorem) in as accessible a way as can be imagined, and explores its consequences in mathematics, computer science, and neuroscience, but is also probably the most entertainingly and clearly written work of non-fiction I've ever encountered.


Feynman

The Feynman Lectures on Physics: It's everything. Probably the most detailed discussion of physics concepts that you'll find on this list.

Burke

Connections: Not exactly what you were asking for, but I love it, so you might too. James Burke traces the history of a dozen or so modern inventions, from ancient times all the way up to the present. Focuses on the unpredictability of technological advancement, and how new developments in one area often unlock advancements in a seemingly separate discipline. There is also a documentary series that goes along with it, which I'd probably recommend over the book. James Burke is a tremendously charismatic narrator and it's one of the best few documentary series I've ever watched. It's available semi-officially on Youtube.

Hooray, a question I can answer!

One of the problems here is that the question is worded backwards. Binary doesn't combine to give us programming languages. So the answer to your question is somewhat to the contrary: programming languages were invented to ease the tedium of interfacing using binary codes. (Though it was still arguably tedious to work on e.g. punched cards.) Early interfaces to programming machines in binary took the form of "front panels" with switches, where a user would program one or several instructions at a time (depending on the complexity of the machine and the front panel interface), using the switches to signify the actual binary representation for the processor functions they desired to write.

Understanding how this works requires a deeper understanding of processors and computer design. I will only give a very high level overview of this (and others have discussed it briefly), but you can find a much more layperson accessible explanation in the wonderful book Code: The Hidden Language of Hardware and Software. This book explains Boolean logic, logic gates, arithmetic logic units (ALUs) and more, in a very accessible way.

Basically, logic gates can be combined in a number of ways to create different "components" of a computer, but in the field of programming languages, we're really talking about the CPU, which allows us to run code to interface with the other components in the system. Each implementation of a processor has a different set of instructions, known as its machine code. This code, at its most basic level, is a series of "on" or "off" electrical events (in reality, it is not "on" and "off" but high and low voltages). Thus, different combinations of voltages instruct a CPU to do different things, depending on its implementation. This is why some of the earliest computers had switch-interfaces on the front panel: you were directly controlling the flow of electricity into memory, and then telling the processor to start executing those codes by "reading" from the memory.

It's not hard to see how programming like this would be tedious. One could easily write a book to configure a machine to solve a simple problem, and someone reading that book could easily input the code improperly.

So eventually as interfacing with the machine became easier, we got other ways of programming them. What is commonly referred to as "assembly language" or "assembler" is a processor-specific language that contains mnemonics for every binary sequence the processor can execute. In an assembly language, there is a 1:1 correlation between what is coded, and what the processor actually executes. This was far easier than programming with flip-switches (or even by writing the binary code by hand), because it is much easier for a human to remember mnemonics and word-like constructs than it is to associate numbers with these concepts.

Still, programming in assembly languages can be difficult. You have to know a lot about the processor. You need to know what side-effects a particular instruction has. You don't have easy access to constructs like loops. You can't easily work with complex datatypes that are simply explained in other languages -- you are working directly with the processor and the attached memory. So other languages have been invented to make this easier. One of the most famous of these languages, a language called "C," presents a very small core language -- so it is relatively easy to learn -- but allows you to express concepts that are quite tedious to express in assembler. As time has gone on, computers have obviously become much faster, and we've created and embraced many languages that further and further abstract any knowledge about the hardware they are running on. Indeed, many modern languages are not compiled to machine code, but instead are interpreted by a compiled binary.

The trend here tends to be making it easier for people to come into the field and get things done fast. Early programming was hard, tedious. Programming today can be very simple, fun and rewarding. But these languages didn't spring out of binary code: they were developed specifically to avoid it.

TL;DR: People keep inventing programming languages because they think programming certain things in other ones is too hard.

I'm not a professional in the field, but my favorite free-time science books are usually focused on evolutionary biology, so here goes. One of the best discussions on this particular topic I've read is in The Ancestor's Tale by Dawkins. It's an excellent 3-page discussion you can read in full by accessing the "Look Inside!" preview of the book on Amazon (link to book page) and scrolling to the bottom of page 430. Do this by searching for "Maynard Smith" and clicking on the result on page 430. You'll need to sign in in order to search.

Anyways, I'll try to summarize the discussion here (although I'm a huge fan of Dawkins' eloquence in this book so I'm afraid I won't do it much justice). At a fairly naive level, sex is an evolutionary paradox. Modern Darwinism says that every organism strives to pass on as many of its genes as possible to its offspring. If this is true, however, why does sex, which is basically throwing away half of your own genes and mixing them with half of those of some other stranger, make any sense? An asexual organism can pass on 100% of its genes to its offspring. A sexual organism can only pass on 50%.

And yet, sexual reproduction is pretty much the norm for multi-cellular organisms. This suggests that the "twofold" cost of sex is somehow "cancelled out" by some other advantage of having two parents. One possibility is if the male commits to the child (instead of just running off to have sex with some other female), the couple can, as a group, produce at least twice as many offspring as the asexual alternative. While it is true that the male puts as much effort into child-rearing as the female in a few species, (emperor penguins, for instance), it is by no means the norm. So there must be something else going on.

Genetic recombination Dawkins hesitates to say that it alone is sufficient to counteract the massive twofold cost of sex, but it is definitely a factor.

----------------------

After this Dawkins makes some points that are very interesting but not totally relevant to your question, so I'll just summarize it very quickly. High school biology teaches us that genetic recombination introduces diversity and variety to the gene pool. Dawkins makes the point that sexual reproduction simultaneously has the opposing effect as well because it introduces the very concept of a gene pool. Think about it: an asexual organism shares none of its genes with its brethren. The very idea of a gene pool is nonsensical. In fact, you could say every new creature is a separate species because from that moment on, it's evolutionary path is completely different from that of its brother or sister. Yes, sexual reproduction, through the process of genetic recombination potentially allows for greater diversity and variety. But sexual reproduction introduces a gene pool that tends to diffuse the effects of genetic recombination. Gene pools have a massive "inertia" that a single wayward member cannot easily change. Dawkins forwards this not necessarily as a benefit of sex, but rather a consequence of it.

Perhaps a lot will be clearer if you get the quantum nature of the measurement of light's polarization. Classically, light is a transverse electromagnetic wave. When one measures a photon's polarization it assumes a definite value, i.e. some orientation. To say that light is unpolarized means that all electric field directions of every photon in a beam will have equal probability to be measured. If the light is polarized then it can be measured in one of only two states. "Circular polarization" means each possible state is described by a plane waves of equal amplitude but differing in phase by 90°. If the light is "elliptically polarized" then it's unmeasured state is described by two simultaneous plane waves of differing amplitude related in phase by 90°. It can also be called elliptically polarized if the amplitudes of the two states are equal but the relative phase is other than 90°. So an unpolarized beam of photons say, or a single photon with a polarization at some angle relative to your measuring polarizer say, is not split into two when sent through a polarizer, rather each photon takes one path or another according to probability.



Concerning your next group of questions about how light propagates through dielectric solids like glass... There is only free propagation, absorption, and scattering. Scattering can be either elastic or inelastic. Scattering theory is a rich subject because materials are so diverse in composition. The most common form of scattering in isotropic media like the atmosphere and dielectric solids composed of small molecules is an elastic form of scattering called Rayleigh scattering. Rayleigh scattering occurs when a photon penetrates into a medium composed of particles whose sizes are much smaller than the wavelength of the incident photon. In this scattering process, the energy (and therefore the wavelength) of the incident photon is conserved and only its direction is changed. Rayleigh scattering has a simple classical origin: the electrons in the atoms, molecules or small particles radiate like dipole antennas when they are forced to oscillate by an applied electromagnetic field. This is not an absorption and re-emission. If the scattering sources are stationary, then this secondary radiation is phase locked to the driving electromagnetic field. So perhaps this is what you mean by "coherent transmission". But even for a truly coherent source of photons, from a laser say, the coherence length is shorted by the presence of the dielectric.



Lastly, your bonus question... You need to read Richard Feynman's, QED: The Strange Theory of Light and Matter. Light propagates as a wave, even single photons. It therefore takes all possible paths, not just the path of least time! It's just that only those paths which arrive at the detector in phase will result in a non-zero amplitude. And for a single ray of light passing from one isotropic medium to another of different index of refraction, there is only one path that satisfies that condition, the path of least time. Anyway, you will love the book and will come away understanding light much better.

I've looked into this quite a bit myself, psychology/biology background here with lots of readings of anthropology. There are many ways in which humans can order their societies, and it's quite typical for every culture to believe its way is not only the best and most sensible, but natural - "the way things are."

This is a touchy topic, and one that is dangerous to talk about because of the inherent risk of questioning deeply-held values within a culture. Many things are taboo, but I think it's worthwhile to try to understand who we are as human beings, and part of that will have been shaped by our history - evolutionary as well as culturally. There are many myths out there about love and sex, and they can cause lots of pain and heartache. In general it's worth examining beliefs to ferret out ideas that exist at the expense of humans, and discard those that have more costs than benefits.

By far the best survey on the subject is a recent book called Sex at Dawn. If you are interested in the topic, I suggest reading it - I've come across many of the things talked about in the book from other sounds sources, and the book is impressive. It's scientific and evidence-based, and the authors take great care with the subject because they know it's touchy. It's also pretty damn entertaining and written at a very accessible level for having such detailed information.

I have heard great things about KhanAcademy. As far as books go, for Humans, the course I co-teach uses Human Evolutionary Genetics: Origins, Peoples & Disease (ISBN 0-8153-4183), but I would definitely brush up on basics before reading that one -its definitely a text book, but a great reference. A more general book might be Why Evolution is True , and I like 'Survival of The Sickest' for some general knowledge on why some diseases tend to stick around (which you would think would go away...). I hope that helps, that's about all I can think of off the top of my head right now. PM me if you have any questions too, I love talking about genetics. :)

Disclaimer: I am an engineer, not a physicist, biologist, etc.

I've always been partial to Feynman's writings when it comes to non-technical discussions of physics. Six Easy Pieces is a great place to start, and if you enjoy it, you can try out Six Not So Easy Pieces. QED is a very accessible book on quantum electrodynamics. Don't let the complex-sounding title fool you--Feynman makes this subject very easy to understand for the layperson.

I really enjoyed reading Relativity for the Million by Martin Gardner, although it's been quite a while since I read it. Gardner is a great author, and this book is perfect for the interested layperson. If you enjoy puzzles, check out his other books. If you want to get a little more technical, Relativity: The Special and the General Theory by Einstein is a good choice.

If you're up for a challenge and willing to commit to a bit of study, I recommend The Road to Reality: A Complete Guide to the Laws of the Universe by Roger Penrose.

As far as magazines go, I've found that Science News keeps me up-to-date on the latest developments in science without getting mired in the details of subjects that I may not be familiar with.

I'm just glad I could help. I would recommend for you the book QED: The Strange Theory of Light and Matter, which is a transcription of four lectures by Richard Feynman.

If you don't know who Richard Feynman is, he's one of the people who won a Nobel prize for the formulation of Quantum Electrodynamics (the interaction of photons with charged particles like electrons). But more importantly than that, Feynman was EXCELLENT at talking about science in a manner that laypeople can understand, without actually dumbing down the material. These lectures explain QED in straightforward English. I strongly recommend it, it's definitely worth the $12. Hopefully this book will be a jumping-off point to further learning for you (as it was for me). Enjoy!

Here's the thing about optics for astronomy. The reason that we can't see stuff isn't because it's very far or small, but because it's very dim. To see the most interesting things in the sky, you don't really need to zoom, but just collect more light (effectively make your pupil larger). It's also comparatively much less expensive to make a larger light collector than it is to make something with a lot of zoom. Zoom is good for looking at the moon or Jupiter. Light buckets are better for everything else, like galaxies or nebulae.

So my advice to you is to look at 2 options. 1st is a "dobsonian telescope" which is basically a big tube with a concave mirror at the bottom to direct something like 12" of light into your 1/4" pupil. $3000 is more than you need, and many people actually just build them, because the mirror to eyepiece alignment is the important part and the rest is just for making it easy to aim, adjust and transport. The 2nd thing which I recommend you can do inexpensively right now is to buy some astronomy binoculars and a basic camera tri-pod to mount them on. With these you'll be able to find tons of stuff. Most of the stuff you'll look for with 12" dob scope, but just with less definition. These are the ones that I have and they're great!

I was in the exact same place as you near the end of my undergraduate years. I started college with the idea of getting an MD and joined a lab only to pad my application to medical school. After shadowing doctors, volunteering at free medical clinics, and working in two different research labs, I finally decided to do the PhD. I even went so far as to take both the MCAT and GRE. That turned out to be a good thing since I did well enough on the MCAT to teach MCAT prep for Kaplan and supplement my meager PhD stipend. Have you considered a combined MD/PhD program?

1. A PhD generally takes five years, but the range of people I know is from 4-7 years. The nice thing is that there is no debt. You get paid to go to graduate school. It's not much, but it's enough to live on.
   
   
2. The job market is pretty diverse actually. Academia is certainly a very common path, but tenure track jobs are hard to come by right now. There are lots of opportunities in industry (biotech, pharma), government (policy, advisory roles), legal (patent), or anything where an analytical mind and the ability to quickly adapt to new information is important. I know people who have gone on to all of those types of positions. None of my grad school colleagues are unemployed, but some of them have had to change their paths when their first choice didn't work out. I don't know about more comprehensive statistics on the job market for PhDs though.
   
   
3. If you want to learn more about basic neuroscience, I would recommend a textbook like this one:
   http://www.amazon.com/Principles-Neural-Science-Eric-Kandel/dp/0838577016
   It's a bit out of date, but it's widely regarded as one of the best basic neuroscience textbooks out there. I keep hearing rumors of a new edition, but the release dates keep changing.
   Depending on your level of skill and access, you could always check out new issues of the journals Neuron or Nature Neuroscience. It's a good idea to know a bit about what interests you so you can target your grad school applications.
   
   
4. Right now? Probably cancer. We don't know enough about how to work with these cells yet.

Eh, first you have to read up on quantum mechanics and get a decent understanding of quantum mechanical spin and quantum numbers in general. Something like Shankar - Principles of Quantum Mechanics, though there are tons of textbooks on it. You won't really get into particle physics, but should read at least to the point of understanding addition of angular momentum and spin (typically in context of hydrogen atom).

Then a text on particle physics like Griffiths' Intro To Elementary Particle Physics. (You could also start Griffiths' Intro to QM).

You could also consult free resources like the particle data group, but their reviews will be largely gibberish if you don't understand the basics of QM / particle physics / group theory. (Articles like Quark Model, or Naming Scheme for Hadrons).

If you are looking at hobby-level interest without getting into any math/textbooks, the best I can suggest is Feynman's QED but it won't talk about isospin or hadrons or particle naming conventions but is a great layman introduction to quantum electrodynamics.

Hello! There are many things we still don't understand about the aurora. Some of these things are discussed in the final chapter of my book, Aurora: In Search of the Northern Lights. I think what I would be most interested to find out is whether there is any affect of the aurora on the weather. The systems are quite separated because the aurora occurs high in the atmosphere (generally around 100 km/60 miles up or above, whereas our weather systems are generally below 20km, so there is a big difference. But sometimes people notice connections. A Sami reindeer herder in northern Norway once told me that they see good aurora when the weather is changing. It would be nice to know whether this is true. Perhaps there are processes of particles filtering down (though this would be slow), or waves propagating or.... I don't know. There are still things to find out.

The most captivating aspect? I love it when I see movement and colour. This only happens in more active displays but I love it when it moves quickly. It make me yelp and jump and just want to go back and see it again. It can do this thing that reminds me of a pianist doing a glissando on the piano. The light moves in flashing pillars across the sky that makes me think of someone running their hand along the piano and the keys going up and down in order. It's beautiful.

Here's the book link if you're interested: https://www.amazon.co.uk/Aurora-Northern-Dr-Melanie-Windridge/dp/0008156115/ref=tmm_pap_swatch_0?_encoding=UTF8&qid=1460708740&sr=1-1

The answer to this is much, much deeper than any of the comments so far. The answer to "How does" is not "4%". The answer is in Quantum Electrodynamics.

I have to run to work, and Richard Feynman is much better at explaining things than me, so I'll point you to his book QED which is dedicated to answering this question as a way to explain QED.

Sorry to have to run because this is fascinating, but to give an accurate answer that really hits on the principles behind it, takes about 20 pages from one of the smartest men who ever lived. I couldn't recommend the book more - it is accessible to anyone of reasonable intelligence willing to read it carefully, and unlocks one of the great mysteries of nature in an entertaining and exciting way.

> Cultural beliefs do actually influence ways of thought, scientific method included

The scientific method is not a "way of thought". It's a method. You're not providing any evidence to support that claim. The fact that different cultures have different patterns of thought is well-established, the idea that this makes science culturally relative is not. Are you saying logic is culturally dependent as well?

> Westerners tend to rely more on formal logic and insist on correctness of one belief over another when investigating conflicting opinions or theories, while easterners consider all the interacting environmental relationships,

A vague and unsubstantiated orientalist over-generalization if I ever heard one.

> One can even argue the Scientific Method is actually an invention of the western tradition

The automobile is a western invention too, and yet the Japanese understand them just the same way as we do.

>TL;DR: read something like The Geography of Thought for intriguing trends in how your Asian lab partner interprets data differently from you.

I've never run across a case where he did. Read a good book on philosophy of science to understand why natural science strives to eliminate bias, including cultural bias. It's not contingent on it but the exact opposite.

>Difference being Goswami was a quantum physics professor

There's no such thing as a 'quantum physics professor' or really a 'quantum physicist'. All physicists study quantum mechanics and nearly all use it, to different extents. Goswami's actual expertise is apparently nuclear physics, which does not imply any greater understanding of the foundations of quantum mechanics than that of most physicists.

> who wrote respected college textbooks

As far as I can tell, he's written one textbook on introductory quantum mechanics. I've never heard of him or his textbook before, and I see little reason to believe it's 'well-respected' or popular, as it only has 5 amazon reviews, as compared to 70 for Griffiths, an actual well-regarded textbook. Sakurai's "Modern QM" and Shankar's "Principles of QM" are popular and well-respected as well. Griffith's is also known for the consistent-histories interpretation of quantum mechanics, while the latter two are 'Easterners', yet don't subscribe to any of this kind of nonsense.

> My background is not in quantum physics, but sooner or later you guys will have to (you should?) reconcile your understanding of reality with how different cultural traditions interpret reality.

You haven't shown any depth of knowledge about 'cultural traditions'. You've made gross generalizations and outright false statements about these things. Calling Western philosophy 'materialist' while 'eastern' is supposedly uniformly 'idealist' (both terms are from Western philosophy) is flat-out wrong.

> Furthermore, the jump is discontinuous in that the electron is never in any orbit not defined by one of the probability clouds.

That's saying that mixed states and quantum superpositions do not exist. It's wrong, and introductory level understanding of formal quantum mechanics is enough to know it.

>Can you please point me to a more accurate description?

Show that the eigenfunctions of the electronic Hamiltonian are no longer eigenfunctions under the action of a perturbing external electromagnetic field.

> What is the interesting part of the delayed-choice experiment then if it's not that what we observe depends on how we measure it?

Did you make any effort at all to find out on your own, such as reading the wikipedia article? I don't see why I should spend time explaining it otherwise. The fact that "what we observe depends on how we measure it" is already evident in the double-slit experiment.

> the most interesting scientific discoveries come when interpretations of science and philosophy butt up against each other.

No, they don't. The most interesting scientific discoveries come when a well-established theory is proven wrong. Metaphysics has nothing to do with science. The Bell test is not philosophy, it's science. It's an empirical test of an empirically-testable thing.

> it appears that a non-local signal (that is, a deliberate faster-than-light transmission) is impossible

It's not the Bell test that says that, it's special relativity.

> Help me understand reality as you interpret it.

Now why the heck would I spend any time on doing that? There's a huge number of good, factual popular-scientific books on quantum mechanics and modern physics. There are plenty of good textbooks. There are good books on science and philosophy of science as well. But instead you waste your time on reading Goswami's nonsense, which would clearly be out of the mainstream to anyone who'd bothered to do a modicum of web searching beforehand. Then you defend it all, basically by stating that you know better than an actual scientist how science works.

You haven't shown that you've made even the slightest bit of a good-faith effort to understand either science, the scientific method and mindset, or established quantum physics. To me it appears that you came here seeking confirmation of what you'd already decided you wanted to believe.

Stephen Hawking, Brian Greene, Carl Sagan, Richard Feynman, Neil Tyson, Stephen Weinberg and Murray Gell-Mann, among others, have all written good popular-scientific books on modern physics. Just about all of them say something about quantum mechanics and the more popular interpretations of it. And for a more in-depth study of the philosophy of science surrounding quantum mechanics, read e.g. Omnes' "Quantum philosophy".

I think the best answer is: since photons don't come with nametags, there's no way to tell, but in most cases, the light behaves as if it's the same photon. There are however some properties of light (diffraction, for instance) where thinking of each point in space as a source of new photons is useful.

For extra credit: the same is true of matter.

Not 100% related, but for more on this sort of thing check out Richard Feynman's short book "QED: The Strange Theory of Light and Matter". It's intended for ordinary laypeople, which says a lot about Feynman's confidence in laypeople, but it's great for the dedicated reader.

I don't have the book to hand to check for the exact quote (and his references) but the excellent pop-sci A Short History of Nearly Everything mentions this in a similar context, but notes that a certain amount of time has to pass to ensure complete dispersal of the atoms in question.

So while it might be true of things some thousand years ago, the probability of this being true for this a maximum of ~3-4 decades is significantly decreased.

Obviously the type of element is going to matter a lot - solids migrate slower than liquids, and much slower than gases, but I'm not even sure how you'd put a proper number on it.

This seems like something of a Fermi Problem to me. It's quite possible that Avogadro wins, and 10^23 * $really_small_probability has in fact happened.

Looking on their website it seems as if they do not let outside people borrow from their library, sorry :(.

I know many libraries have "partnerships" for the lack of a better word, where if you try to borrow a book from the library, and they don't have it, they will request it from somewhere else they are partnered with and get it for you.

Some ideas of books:

For my undergraduate astrophysics class I used - Foundations of Astrophysics by Ryden and Peterson, ISBN13: 978-0-321-59558-4

I have also used (more advanced, graduate level) - An Introduction to Modern Astrophysics by Carroll and Ostlie, ISBN13: 978-0-805-30402-2

There are plenty of other undergraduate text books for astrophysics, but those are the only two I have experience with.

Some other books that may be just fun reads and aren't text books:

A Brief History of Time - Hawking

QED: The Strange Theory of Light and Matter - Feynman

Random popular science books:

Parallel Worlds - Kaku (or anything else by him Michio Kaku)

Cosmos - Sagan

Dark Cosmos - Hooper

or anything by Green, Krauss, Tyson, etc.

Videos to watch:

I would also suggest, if you have an hour to burn, watching this video by Lawrence Krauss. I watched it early on in my physics career and loved it, check it out:

Lawrence Krauss - A Universe From Nothing

Also this video is some what related:

Sean Carroll - Origin of the Universe and the Arrow of Time

Hope you enjoy!

Edit: Formatting.

> do you mean that they are man-made tools to help picture and calculate and predict?

Yes.

> once we figured out that light is the oscillation of the EM field, that proved to us that fields are actually a real physical... thing.

That's definitely not the case (the second part.) In fact the experiments of Michelson and Morley are usually cited as definitive proof that it's not a real, physical thing.

> If you don't feel confident answering, are there any books you would refer me to?

Check out Feynman's books "6 Not-So-Easy Pieces" and "QED". QED is the one more relevant to this discussion. I would also recommend Roger Penrose's The Road to Reality if you have a lot of spare time and are willing to keep up with it properly.

Are you taking an intro to physics course as an undergraduate? If so, and if you are interested enough to take more coursework on physics, try taking an EMags (Electromagnetic Fields) class in the EE or physics department. 20th century physics (relativity) and a couple of QM (Quantum Mechanics) classes would be helpful as well. After you take a couple of EM and QM courses, you'll really appreciate how god damn hard it is to have any sort of "intuition" about physics, and how important it is to just treat the math like math.

Well, if you can sink as much time into Wikipedia as I can, that's a good start. And don't skip the references and links at the bottom; that's 90% of the fun!

There are a lot of good, popular-audience books on these topics. I don't know any about BCI in particular, but check out The Man Who Mistook His Wife For A Hat (and other stuff by Oliver Sacks) and Phantoms in the Brain. Those are the ones we read in COGS 1 and they're great. Right now I'm reading Jonah Lehrer's Proust Was a Neuroscientist; How We Decide was also good. Also, don't shy away from academic literature. It's not really so hard to read if you're interested.

Are you or could you be in college? Check my advice here. If you at least live near a college, sit in on some classes. Write to a professor and see if there's lab work to do, maybe as a volunteer. That could get your foot in the door.

The Turing machine answer is a fantastic theoretical one, but if you want to see a practical answer for "how do you build a computer (like most people would think of a computer) from scratch", which seems to be what you were looking for when you wrote this:

> What is going on at the lowest level? How are top-level instructions translated into zeroes and ones, and how does that make the computer perform an action?

...then this book is a fantastical down-to-earth, extremely approachable first read for such things (and designed such that you don't need *any* prior knowledge to start reading it).

Seriously, if you want to dive a little bit deeper, I highly recommend it.


edit: seems someone already recommended Code. Still, can't give it enough praise. Or The Elements of Computing Systems (TECS) which a (only *slightly*) more technical read designed around building everything that a computer "is", piece by piece...

Edit2: And as for "what's going on with the Minecraft ALU", TECS is a good read there as well, since the machine described in that book is what I based the ALU on. Also, the fact that Minecraft can simulate logic gates is what links the "real world" and the "minecraft world" together, because logic gates are all you need to build any computer (that's how Minecraft can let you build Turing Complete devices)

Indeed yes, there isn't so much absorbtion and reemission of quanta as i understand it as does the substance act like a matrix or diffraction grating. Then within the substance you have lots of little broken up waves all interacting with each other, canceling each other out in parts and bolstering each other in others. The 'super wave' made up of all these interactions propagates at slower than light speed, and potentially at an angle. Come out the other side (into a vaccum again) and there's no diffraction, no 'super wave' but back to light propagating at 'light speed again'.

There's probably a good quantum analogy too, but I don't recall it.

The thing to always remember is that these forces aren't quantum particles or idealized waves, those are just the best models we have for something we don't fully understand.

Read Feynman's QED, its short, written for the layman and completely awesome. It will also blow your freaking mind.

I'm going to be a little over-focused on textbooks, but I think the best treatments of these topics begin to move out of the "popular science" book territory.

For regular gravity, if you have decent linear algebra (matrix math), vector calculus skills (divergence, gradient, curl and the like), and preferably some familiarity with Lagrangian mechanics then I'd recommend Hartle's Gravity. I think that's pretty much the minimum set of prerequisites to be able to do General Relativity and see gravity come from that.

It doesn't hurt that the same math is pretty much what you need for basic quantum mechanics; but you need a much longer sequence to get to quantum field theory, the point where you can start doing the necessary particle physics of the problem.

According to Willpower:Rediscovering the Greatest Human Strength it is. I read the book a few months ago. I'm a little fuzzy on the details but from what I remember it said some of the following interesting points on willpower

• It can be fatigued. If you use your willpower to do one thing you will be less able to do something else later.
  
  
• You can use an endless supply of tricks to conserve your willpower. (see the marshmallow experiment
  
  
• As many people said it's linked to feel good neurochemicals like Dopamine (I forget what exactly they mentioned in the book). Also it's linked to blood sugar. Hungry people have less self control for everything even for things that have nothing to do with them eating.
  
  
• You can strengthen it by excising it. Just ask David Blaine
  
  Over all if you have an interest in willpower at all I recommend the book. However don't expect any magic tricks from it that give you unlimited willpower, this list covers what I thought was most useful.

Yep, many physicists subscribe to the "shut-up-and-calculate" school of thought.

OP - although physics can't really address some of your specific questions, the mathematical link between the quantum and classical regimes is quite clear: if one considers the limit of a quantum system with a very large number of particles (e.g., every single atom in a rock), then the properties of the set of particles will be more clustered around their average values. These average values (expectation values) exactly match the classical predictions for that set of particles.

There's a great chapter that goes through all the math pretty clearly in R. Shankar's Principles of Quantum Mechanics.

I'm late to see your comment, but you may find this interesting:

Coral produces annual rings and daily rings. If you add up the number of daily rings between annual rings, then you can figure out how many days were in that year.

Radioisotope dating showed that some fossilized coral that had been found was about 380 million years old.

Now, 380 million years ago, days were shorter, about 22 hours long. So there were more of them in a year.

To find out whether the day really was 22 hours long when the coral lived, they just counted the rings (or made a grad student do it).

Turns out that there were 400 daily rings between each annual ring, which correlates to 21.9 hours a day.

21.9 is close enough to 22 to feel pretty good about it. A great example of different parts of science coming together to verify each other.

Source: Why Evolution is True, by Jerry Coyne

If you want a very good overview of how computers work, you should try reading the book Code. It starts off talking about codes, like Morse Code and Binary. Then it moves on to light switches and batteries, and other neat constructions you can make with switches and relays, then it shows you how to build a simple adder. By the end of the book the author has basically given you an overview of how computers work from the logic gates all the way up to the processors and operating systems. It's a really good book, and each chapter flows pretty well to the next and it explains things in ways that are easy to understand.

I was also kinda "upset" about quantum mechanics before I really studied it. The popularizations made me intrigued, but unsettled about the whole thing. Actually taking the material and understanding it a little better really did help with that. If you're planning on taking a class in it, that's great. If you're talking about self-study, I though that Griffiths was a great introduction.

Do you want a formal understanding? If so, then there's a problem. The 4 fundamental interactions are not completely understood. The electromagnetic is very well understood and is covered by quantum electrodynamics. The weak interaction is also understood quite well and has been unified with the EM interaction into the electroweak interaction.

The strong interaction and gravity are not as well understood. There is no widely accepted theory of quantum gravity (gravity is currently described by general relativity). The strong force is described using quantum chromodynamics (QCD), however QCD is vey complicated (due to the fact that gluons carry color charge and interact with each other).

If you fine with that, then I have to ask, are you comfortable with classical physics? If not then start there. If you are, then you can continue on with quantum physics, this book is a very good quantum mechanics book.

If you want a lay person understanding, then I suggest you do some searches here on askscience, because there is a wealth of information regarding particle physics here.

One more thing, very few people call it "quantum physics", it almost always goes by the name "quantum mechanics".

In addition to the links already posted, I'd add Baumeister with his excellent work on willpower (link on amazon)

Also probably the most useful piece of research I found was in Handbook of Self-regulation, specifically a piece by Alexander Rothman, Austin Baldwin and Andrew Hertel. (here's the link on google books - warning, it's not light). Some of it is also in the Baumeister book above.

Long story short, the most useful approach is to set up things so that you don't need willpower in order to work, and that's best done by creating habits. There's lots we know about the science of creating habits, easily enough to make it doable.

I'd recommend you read A Short History of Nearly Everything by Bill Bryson. It's a pretty good survey of natural science and very accessible to the layman. I think I've read it twice and each time come away with that "everything in the universe is awesome" feeling. It's probably my favorite non-fiction overall.

Imagine an electromagnet wired to a battery, with a switch as well. When switch is CLOSED, the circuit is complete, and the electromagnet becomes magnetized.

Now imagine a metal flap on a hinge, close enough to the electromagnet such that when the electromagnet is magnetized, the flap moves toward the electromagnet, and when the electromagnet is not magnetized, the flap moves the other way.

Now imagine that this flap is also connected to the battery on one side, and a light is connected on the other, such that when the flap is moves towards the electromagnet, it completes a circuit; so the light turns on. So now think of this flap as another switch, except this switch is OPEN and CLOSED by the electromagnet; which is controlled by our manual switch. SO: when I CLOSE my manual switch, this CLOSES the flap, and thus the light turns on, and when it is OPEN, this OPENS the flap, and the light turns off.

Like this.

This electromagnet/flap contraption is a relay. And once you have wrapped your head around this clever device you will understand the basis for how computers work. It may seem like there's not a lot to grasp here, but there's actually quite a lot.

For example, if you agree with me that this circuit is a device we could make, then you could imagine that we could arrange different configurations of switches and relays. For example: imagine a configuration with two switches, such that the light turns on when two switches are both CLOSED, but the light is off when at least one switch is OPEN. Or, imagine an "opposite" relay, such that when the switch is CLOSED the light turns off, and when it is OPEN the light turns on. Or, imagine a circuit with two switches such that the light turns on when on one switch is CLOSED or the other is CLOSED, but not both or neither.

What we are doing here is building logic gates, and this is the basis for computing. Today's computers don't use electromechanical switches like this, but they used to. Today they use very tiny transistors. Enough logic gates configured correctly will give you the basis for a microprocessor, or RAM.

This diagram and the concepts presented were lovingly stolen from this book, which I highly recommend if you'd like to know more.

I really enjoyed reading The Age of Wonder by Richard Holmes.

Also Thunderstruck by Erik Larson.

Both of these books are fantastic nonfiction accounts of the history of scientific discovery.

On the biology side, anything by Dawkins is a good choice. I recommend The Greatest Show on Earth

My gateway drug was The Panda's Thumb by Stephen Jay Gould

Wow, thanks for the Reddit gold, that's awesome! It's been my pleasure to have the discussion with you. As for a good textbook, I have a few suggestions. For a pretty good broad look at optics from both classical and quantum points of view, give Saleh and Teich a look. For purely quantum stuff, my undergrad textbook was by Griffiths, which I enjoyed quite a bit, though I recall the math being a bit daunting when I took the course. Another book I've read that I liked quite a bit was by Shankar. I felt it was a bit more accessible. Finally, if you want quantum mechanics from the source, Dirac is a bit of a standard. It's elegant, but can be a bit tough.

I strongly recommend A Short History of Nearly Everything. The guy does excellent job to go through a lot of stuff, including life.

I will drill on the "to develop" part of your question.

Basically, life as it exists now (and including us) had astonishingly "lucky" brakes. Even global disasters were needed to progress thus far. Having in mind that, I think it is very hard to define what would be better (e.g. there were stages when Earth's atmosphere would be deadly for most modern organisms, but life was present even there and probably in huge amount). Maybe some compounds/conditions would be more beneficial to life but in a lab environment. Our planet was far from that.

Another good point is that life's primary goal seems just "to be". Nothing more, nothing less. In this sense all those coincidences were neither "astonishingly", nor "lucky".

If you're really interested in this kind of stuff, check out The Ancestor's Tale by Richard Dawkins. In it, he examines our common ancestors with other life in backwards chronological order (our common ancestor with chimps, then our and chimps' common ancestor with the other apes, then apes' common ancestor with all primates, etc). There's lots of interesting information about how genes express and get selected for. For example, one particularly fascinating chapter covers the origin of our tri-chromal color vision, as opposed to the vision of most other mammals, like dogs, and what happened in our genes to bring about that change.

I know this isn't what you requested, but as a high schooler, I enjoyed In Search of Schödinger's Cat.

The top level presentations on QM are very light on math, and anything below that brings out heavy linear algebra, differential equations, calculus, etc. So you've probably got that top level covered, and now you need to start solving problems. You could get credit for your efforts by picking one of the undergrad versions of QM from the Chemistry and/or the Physics depts.

I took the chemistry route, so we used Atkins, Cohen-Tanoudji, etc. For all the classes that I took and TA'd, the professor might recommend a book, but rarely reference it.

It may help not to think of it in terms of what advantage it provides to the individual, but rather what advantage it provides to the genes.

It basically comes down to the fact that genes which compelled the individuals who carry them to reproduce (or gave them a better chance of survival) are those that were passed down to the next generation.

So, generally speaking, the organisms alive today are the descendants of those previous organisms who's genetics most strongly compelled them to reproduce (and they are composed, roughly, of those same genes, so that compulsion will be present in them too).

Richard Dawkins's The Selfish Gene does a phenomenal job of explaining this way of thinking.

/u/Millcrab is correct. The fact is we don't have enough time to wait for life to develop in the lab. However, Stanley Miller and Harold Urey started an experiment in 1953 in which they simulated an early Earth environment and after just two weeks their bottle contained 11 of the 20 amino acids we see today, as well as some hydrocarbons and other organic compounds. They also let some vials sit for 50 years and when modern scientists opened them, they discovered over 20 amino acids, which is more than life uses today! So it's easy to make the building blocks of life, the problem is waiting for them to come together and make life.

If you're really interested in this topic, then I recommend reading The Selfish Gene by Richard Dawkins (fun fact, Dawkins invented the modern word meme [from the greek "mimēma"]!). It describes a pretty cool hypothesis on how life could have originated and Dawkins has a really dry sense of humor that you can pick up from his novel. I will admit that he could be a bit more diplomatic on some subjects though.

Any mechanics text targeted for the standard junior level mechanics course for majors will cover it. I used Fowles and Cassiday when I took it. I'm not really sure what else is standard. The standard text in grad courses is Goldstein, which should be approachable by an undergrad at least. If you're crazy and a classical mechanics junkie like I was as an undergrad, Landau and Lifshitz vol1 is a beautiful treatment (that you unfortunately probably already need to have seen the material once to appreciate. Oh well. Like I said: if you're crazy). The issue here is that sometimes undergrad courses will skip these (as I learned, amazed, when I was encountering other grad students that hadn't done Lagrangian mechanics before) so make sure you read those chapters and do the problems: quantum mechanics is done in a hamiltonian formulation, and quantum field theory in a Lagrangian formulation (the latter is because the Lagriangian treatment is automatically relativistici)

I never had a course specifically on waves. It's something you'll likely hit pretty well in whatever non-freshman E&M course you take. Beware though that some courses targeted at engineers will do AC circuits at the expense of waves. But the text is still useable to look into it yourself.

Quantum Mechanics is not really a subject that can be summed up in a reddit comment. The best way to learn about something is to read about it. Go to your local book shop or library and look for some books on the subject. I've read dozens of books on the subatomic and I still don't understand it fully. If you're aspiring to be a physicist, you should become reeeeeally familiar with reading.

Uncertainty is a good one that I've read. And another great one is In Search of Schrodinger's Cat

The Ancestors Tale

Dawkins gets a lot of hate, but the man knows his evolutionary biology and he can write! This is a great read, and a good overview of human ancestry, and if you're interested in the finer details of natural selection, follow it up with The Selfish Gene.

Recommended reading on the subject. Here's my explanation, though this is outside my expertises, and a physics major should offer a more comprehensive answer. But here we go.

When a photon strikes an atom, it causes an electron to jump to its next energy level. The photon is absorbed in the process, and its energy is conserved by an increase in the electron energy level. The atom won't like the configuration, so the electron will soon drop back down to the lower energy level, releasing a photon. This is called reflection.

Now, when you get enough atoms lined up in the right orientation, the image will be conserved. The book I provided offers an awesome explanation of the phenomena. Simply, the light can be considered to be reflected off the front surface and back surface. You know how light is sometimes thought of a wave? It is useful to think of it in this way for this explanation. The reflections from the back and front surface will interfere (two waves taking up the same space). If a peak meets with a valley, the two cancel. If a peak meets with another peak, it will interfere 'constructively', and the light will be preserved.

Now, if the surface is nice and smooth, a clear reflection will be seen as a result of this interaction between the two lights. reflections off glass windows works in this manner. When you are in a bright room at night, the light reflecting off from the room is brighter than the light coming in from outside. This is why you have a hard time seeing through your windows at night, and it helps to shield the glass from the light with your hands. BUT I DIGRESS

Now, you are correct in thinking that the absorption/emission event sends the photon in a random direction. But the waves associated with these random reflections cancel each other out in most cases. The only photon that survives the mass extinction are the ones that reflected with an angle of reflection equal to the angle of incidence.

But really, read the book I linked. It explains this all much better than I can.

No problem, glad you find it interesting. If you want to know more, Steve Strogatz's Nonlinear Dynamics and Chaos is a good place to start and is generally very accessible. It talks about how to tell what regions of phase space are stable vs unstable, for example, and how chaos arises out of all of this. Overall it is a good read and has a lot of interesting examples (as is typical of a lot of his books).

For more on the Hamiltonian mechanics in particular (albeit at a more advanced level), the classic text is Goldstein's Classical Mechanics. Its definitely more dense, but if you can push through it and get at what the math is saying its a really interesting subject. For example, in principle, you can do a coordinate transformation where you decouple all the generalized momentum - coordinate pairs and do a sort of modal analysis on a system where you would never be able to do so otherwise (these are called action-angle variables)

A sufficient resource for explaining how to get to Classical Mechanics can be found here.

The idea is that if you have quantities on the surface of a geometry and quantities in the tangent bundle(where quantities like velocities lie), then your dynamics can be described by the interaction of the two under a small set of constraints. These constraints are set by the base axioms and principles of your understanding of the system.

Having these, you can formulate your dynamics which ever way you want. In other words, The Lagrangian is an arbitrary choice. Strictly speaking, it is a choice that physicists use because it makes that algebra easier. The Euler-Lagrange equations are the result of this, and can be used to describe the dynamics of the system. Similarly, once conservation laws in the Lagrangian have been established, the Hamiltonian can be calculated, and from there, invariants in the Hamiltonian can be used.

Shubin's Your Inner Fish covered this from an evolutionary/development perspective - an amazingly fascinating read.

In a shortened, abridged summary: The head of a shark is a series of segments where each segment as one vertebra, and in ennervated by nerves from that vertebra, and each vertebra has one gill pair. Nice and logical.

However, in mammals, many of those segments are munged together to create a neck, throat, ears and larynx structures from the gills, and many other components have moved from their original segment into the mess. The new jumbled components are ennervated from their historic segment, leaving some nerves very long and weird paths - for example the recurrent laryngeal nerve exits the spine close to the larynx, loops down to the heart, then back up to the larynx. It all made sense in the shark...

I believe I remember reading that V.S. Ramachandran had an insight to this when he was dealing with phantom limb patients. The area of the brain that maps foot and toe sensations is right next to areas which are involved with sexual stimulation. When an area of the brain (especially involved with perception and sensation) lose their means of input and become disused (as in someone losing a limb), those neurons are gradually recruited by nearby brain regions to supplement their functioning. So, in some cases of people losing their lower limbs, those foot-sensation areas became cross-linked with the sexual stimulation areas causing the people to have a sexual reaction when imagining their phantom toes being sucked on.

This may be a neurological explanation for foot-fetishism, but I don't know off the top of my head if this has been followed up with concrete study; it only suggests an avenue for further experimentation. This also does little to explain some of the other, less common fetishes (tickling, scatalogical). It also doesn't concretely answer the question as far as genetic/environmental. We have genetic dispositions for particular brain areas being more interconnected than others, but environmental factors play a huge role in this as well, especially as far as deviations from normal development during childhood. As such, though I don't necessarily agree with them, I also can't 100% discount ideas like sexual imprinting.

tl;dr: This, like most other neurological questions, is really complex and the answer lies somewhere on the continuum between genetics and environmental factors.


edit: Looked it up to be sure. For those that are interested, this was discussed in Phantoms In The Brain.

Here's a good start.

There's also a great book called Your Inner Fish that covers this topic well. Here's an excerpt that covers the origins of some human traits like hernias, hiccups, and snoring.

You can trace the history of any human trait through comparative anatomy. In this phylogeny, you can see that the evolutionary order of appearance of mammal traits was vertebrae>jaws>lungs>4 legs>Amniotic egg>milk.

I would highly recommend anyone interested in the details at a level the layman can understand pick up Richard Feynman's QED: The Strange Theory of Light and Matter

http://www.amazon.com/QED-Strange-Princeton-Science-Library/dp/0691125759

It is IMO the best physics book aimed at the layman I've ever encountered. It gives a very lucid and detailed explanation of why light behaves the way it does in our everyday world, given the quantum mechanical rules it operates under.

I would read the book The Greatest Show on Earth by Dawkins. It is well written in plain english that is easy to understand and follow.

You should give this book a read Code: The hidden Language Of Computer Hardware and Software By Charles Petzold

It does a great job of explaining how it all works. Loved it and I don't know how to program (Yet).

I think A Short History of Nearly Everything might be what you are looking for.

Not sure it will 100% meet your needs but a great book nonetheless and worth a read.

Consider implementing an ALU which does various things like add and subtract and bit shifts. So, you have inputs A and B from your memories and your program instructs the computer to add them. The instruction for "add" is also sent to the ALU. So how does the ALU "change" it's function to add this time and subtract the next? Look at how a multiplexer works. So for a simple implementation, your ALU can compute both A+B and A-B (in parallel using separate logic gates) and then at the end, based on the instruction, select which to output. You can also try to imagine how a multiplexer can be used to implement various boolean operations by thinking about the truth tables :).

So, if we can build the kind of ALU logic above, the key becomes addressable memories (note that addresses are themselves numbers which can be manipulated using ALU). When you compile and run a program, it is loaded into memory. The instruction and data are read and then fed into logic like above.

If you are interested and have the time, the book Code presents the material quite well and accessibly.

This is my go-to review on the subject, written by the man who won a Nobel prize on the subject: Eric Kandel.

He also literally wrote the book on neuroscience.

Also, microbiology is the study of bacteria, viruses and protozoa. The term you want is cellular and molecular biology.

To be clear, everything you see with the naked eye is not a star. You can see galaxies too, and if you know what you're looking at, nebulae. Take a pair of high powered binoculars out some night and it's like you've never seen the sky. Better yet, get a pair of these. You won't be disappointed.

If you're interested to learn the basic physicality of a computer, I'd recommend checking out a book by Charles Petzold: "Code: The Hidden Language of Computer Hardware and Software."

https://www.amazon.com/Code-Language-Computer-Hardware-Software/dp/0735611319

It's easy to read and provides a lot of insight into how circuitry embodies and propagates information!

I would not read On the Origin of Species to get an introduction to evolution. It is quite long winded, but that was the standard of the time.

I would start with Why is Evolution True by Jerry Coyne and The Greatest Show on Earth by Dawkins. At this point you should have a good grasp on the basics.

After reading these if you want a more technical introduction I would suggests The Selfish Gene by Dawkins.

Oh good! It's even more BS-ey than I had realized!

My knowledge of quantum physics is limited to what one can learn from popular books (1, 2, 3 ). Could you try to explain the differences between the underlying models/assumptions on which Orch-OR is based, and the models/assumptions in established/standard physics? I would appreciate it.

This is a really great book about the topic. It's much simpler than you might think but kind of tricky to explain unless you know a bit of back ground. The book costs less than a tenner and will give you a while different appreciation of how computers work. Well worth a read even if it starts out seeing rather simple.

https://www.amazon.co.uk/Code-Language-Computer-Hardware-Software/dp/0735611319

As per http://www.amazon.com/A-Short-History-Nearly-Everything/dp/0767908171 there was a significant decrease in anti-microbial activity of clothes washing with the advent of detergents which clean at cold or warm temperatures. As the author describes (if I remember correctly) at the scale of the germs in the fibers, it would be like an adult human wrapped in cargo nets. You simply need to kill/injure the organisms with heat.

From what I understand, these "coding" genes are what makes us look drastically different than organisms that share "97% of our DNA" such as the chimpanzee. A good bit of reading in regards to this topic would be Your Inner Fish, by Neil Shubin.

IIRC a mutation in how much muscle to form for our Temporalis (one of the chewing muscles) when we were apes caused a significant change in brain mass because the lack of chewing power/muscle allowed our skull plates to set later in life and therefore a larger, more developed brain. We have essentially the "same" DNA that chimps do in respect to our Temporalis muscle, the biggest difference is how much muscle the coder DNA calls for.

Your Inner Fish is a book about researchers who predicted one of the missing links between fish and amphibians, and then found it. Not a soft tissue prediction, but in the same vein. Great read.

My girlfriend bought me these for my birthday earlier this year. I bring them everywhere I go - especially when I have the opportunity to escape the light pollution barriers of the cities.

I highly recommend downloading Stellarium for you computer, or Google Sky for the android phones. (I'm sure iPhone has something similar). With this tool, you have an interactive star map you can use from anywhere. You can even track satellites!

With high powered binoculars like mine, or larger Newtownian / Cassegrain scopes, my favorite things to look at in the sky are (you can use stellarium or google sky to find them):

• Jupiter and its moons (you can see 4 clear as day, but there are 64 in total!)
  
• Betelgeuse (top left corner red star in Orion)
  
• The Orion nebula (about where the right thigh is)
  
• The moon of course (you can get lost in all of the craters and shadows)
  
• Andromeda
  
• Pleides (M45)
  
• Omega Centauri

Yes, it's an approximation. This is evidenced by effects like the Lamb shift that cannot be explained with classical electrodynamics (e.g. Coulomb's law). One way of putting quantum electrodynamics (QED) is that two charged particles "communicate" with each other by exchanging photons, "telling" each other whether to come closer or farther apart, and by how much. If you're curious, I suggest reading Feynman's layman explanation.

Quantum electrodynamics explains it using probability amplitudes. Rather than treating light as a particle that bounces off at a point where angle of incidence equals angle of reflection, it approaches it using a quantum mechanical approach incorporating the idea that light is also a wave.

Each point on the mirror acts as an absorption and emission surface, and each point can absorb light from the source and emit light towards the detector (angles don't have to be equal). Taking into wave-like nature of light though, there will be constructive and deconstructive interference between adjacent points. It turns out that there is greatest constructive interference for lights of all wavelength at the point where angle of incidence equals angle of reflection.

Since interference is wavelength dependent, you can selectively choose which colours would be preferred over others at certain angles by modifying the mirror surface - this is how diffraction grating works.

You can read more about it in Feynman's QED: The Strange Theory of Light and Matter.

Richard Dawkin's book The Ancestors' Tale goes in the opposite direction -- from mankind back to the common ancestor of all life -- and tries to estimate the generations along the way. At some point before getting to Amoebas, however, he gives up, because the best approximations are complete guesses. But you could get some insight into your question from that book, I believe.

I don't have my copy on me, and Wikipedia doesn't include his estimates. But check it out! Wikipedia Amazon

> And if i then stop accelerating his time will again go slower?

Yeah, I think that would be the case.

I could recommend a textbook on special relativity if that's what you want. Here's a list with a few options that should be good. Also some textbooks on general relativity include introductions to special relativity in the beginning; I'm a fan of Hartle's book but Schutz (in the list linked previously) is also a classic. Though I don't know offhand which books (if any) discuss this particular detail of the twin paradox.

If you're not interested in a textbook, there are definitely "popularized" relativity books out there, but I don't know much about them. I couldn't tell you which books, if any, might include this specific information, and it's even possible for things to be "lost in translation" when authors try to explain relativity without using math. Ultimately the source is learning how to do the calculations yourself.

Read Sex At Dawn Prehistoric Origins of Human Sexuality

Great book that challenges many theories about this.

I'm in the middle of Bill Bryson's book, A Short History of Nearly Everything. He spends a lot of time talking about the people behind important scientific discoveries, and how they all intertwine into our current understanding of the universe. There's a great chapter on nuclear physics which my post is a rough and dirty summary of. :-)

It is probably a little below what you are looking for, and it is coming up on being 30 years old, but In Search of Schrödinger's Cat is a really good place to start for entry level quantum physics.

A Short History of Nearly Everything

The Hole In The Universe

Universe on a T-Shirt

Light Years

Before The Big Bang

Why Does e=mc^2? (and why should we care?)

Your Inner Fish (about evolution)

And just because it was one of my first pop science books, I'll add The Telescope. Which is of course, about telescopes. It's a lot more interesting than it sounds!

Also, someone else mentioned Feynman's book, called QED. It's a great read.

Griffiths > Eisberg > Sakurai > Zee > Peskin

Peres and Ballentine offer a more quantum information oriented approach, read em after Griffiths.

Shankar before Sakurai, after Griffiths.



In that order. Your best bet though, is to find the appropriate section in the nearest university library, spend a day or two looking at books and choose whatever looks most interesting/accessible. Be warned, it seems that everyone and their cat has a book published on quantum mechanics with funky diagrams on the cover these days. A lot of them are legitimate, but make little to no effort to ensure your understanding or pose creative problems.

If you'd like to learn more about problems like this involving genes that don't confer survival advantage in the way you might expect, I recommend reading The Selfish Gene, by Richard Dawkins. It's very entertaining.

How about "Why evolution is true" by evolutionary biologist Jerry Coyne? It's meant to be accessible to pretty much everyone.

I think this book is exactly what you're looking for. I bought it recently and am now half-way through it, and it's fascinating.

Yes, we're fish! Classifications are nested, and they reflect evolutionary relationships. This puts organisms in a context that shows how things are related to each other by descent from a common ancestor. Think of it as an Euler diagram rather than one taxonomic classification precluding another.

We are nested within the clade Osteichthyes (bony fish) -> Sarcopterygii (lobe-finned fish) -> Tetrapoda (four-legged animals) -> Amniota (laying hard-shelled eggs) -> Synapsida (mammals and "mammal-like reptiles" defined by skull characteristics) -> Mammalia (hair, milk, etc.) -> Primates (nails instead of claws, and other stuff) -> Hominidae (great apes) -> Homo (humans and other closely related taxa) -> H. sapiens (us!)

There's a whole book about it.

If you're really interested in this you might want to check out the book "Code", it leads you from the invention of electricity up to how computer programming languages work, step by step, including the stuff that's being talked about on this thread.

And beyond radiometric dating, there is also geology, historical documentation (beer alone was invented over 7000 years ago), evolution (The Greatest Show on Earth: The Evidence for Evolution is fantastic), and ice cores (for example).

Bill Bryson's A Short History of Nearly Everything is a very good read.

The lectures are $2 on the used market. Well worth the price.

He also covers the dual slit experiment and provides a framework in which the results make sense.

Most of my sources are textbooks and wikipedia for a quick search... On my desk I have Molecular Biology of the Cell and Principles of Neural Science both of which are decent reference texts to have on your shelf. Beyond that, I think I can scrounge up a few good reviews on the subject if there's any interest, but this being Reddit, most people don't have access to papers behind paywalls...

If you're interested in physics, I'd check out Richard Feynman's QED.

It's a short book adapted from a series of lectures he gave on quantum electrodynamics. It's written and explained in such a way that someone with no physics or math background can get a huge amount out of the book.

I suggest Bryson's A Short History of Nearly Everything. He's a travel writer who wanted to know the same things, so he asked every smart person he could find and distilled it into layman's terms, while maintaining a level of brevity that Sagan often lacked.

http://www.amazon.com/gp/aw/d/0767908171

The book "Sex at Dawn" pretty much discounts the belief of overall human monogamy. Says that prior to humans settling down and owning property because of agriculture, we were hunter-gatherers and we should have been more like our cousins the bonobos.

It's a fairly recent book, there is quite a lot of cultural/social history over the last 8,000-10,000 years that disagrees, but they have some good arguments that seem to be based on science.

You'd be well served by reading a book called "CODE - the Hidden Language of Computer Hardware". It starts all the way from the simplest electronic circuits, explains how a powered signal amplifier can be turned into an electronic switch (e.g. telegraph relays, and later, transistors), how those switches can be chained together to form logic gates per /u/Corpsiez, how those logic gates can be chained together to form arithmetic units and memory, and finally how to make a simple 8080 CPU and implement ASCII inputs and outputs.

It is super difficult to explain this in a single post so I won't. Instead, I will point you to the best book on computers ever written. This book walks you through the construction of a computer from the very basic building blocks in a way that is completely understandable for a non-expert. I cannot possibly recommend this book enough.

It won't cover more complex concepts like JITs but it will teach you how computer programs get turned into commands and how those commands are executed by the machine.

If you want to get more advanced, this is the book I used when I studied advanced (Lagrangian and Hamiltonian) mechanics: http://www.amazon.com/Classical-Mechanics-3rd-Herbert-Goldstein/dp/0201657023

(for pirates)

The book I used in first year physics was Giancolli, and in second year it was just my professor's crazy handwritten notes. Here are his crazy notes for advanced mechanics; the ones for Newtonian aren't up anymore.

> primary actor

Fair enough, and thanks for the informative answer. I'll definitely check out the book; Richard Dawkins focused on the same concept in The Selfish Gene and came to a similar conclusion through an interesting example with the prisoner's dilemma.

It's been years, but if I recall correctly, numerous participants designed reactions for the scenario. In the majority of cases, the most selfish options won. However, one of the most successful programs said something along the lines of, "Remain silent for every new partnership, but if one particular person betrays you, then accuse them in all future scenarios."

I think the two qualifications he required for "genuine" altruism were that it cannot be reciprocal (for mutual benefit) or kin-related, so I'll have to research for some more specific examples in nature. Or just read Ridley's book. Still, a mechanical equivalent to DNA seems entirely conceivable; mutations are a large part of evolution, so I suppose "computing errors" could register as parallel.

This is the book you want to read. It walks you through every bit of how a CPU works, in an incredibly approachable way. (If you can understand a light switch, you can understand this book.)

If you really want to understand how all things (binary coding, electronic representation, logic gates, microprocessors) come to together I cannot recommend this book enough - Code - By Charles Petzold

Here's the second edition.

Here are some links for the product in the above comment for different countries:

Link: QED is the one more relevant to this discussion.

• UK: amazon.co.uk
  
• Spain: amazon.es
  
• France: amazon.fr
  
• Germany: amazon.de
  
• Japan: amazon.co.jp
  
• Canada: amazon.ca
  
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  This bot is currently in testing so let me know what you think by voting (or commenting).

Try reading Code by Charles Petzold.

Reading material:

http://programmers.stackexchange.com/questions/81624/how-do-computers-work

More:

http://www.amazon.com/Code-Language-Computer-Hardware-Software/dp/0735611319

http://www.lithoguru.com/scientist/lithobasics.html

http://www.nidokidos.org/threads/37201-Intel-Shows-How-A-CPU-Is-Made-(-Text-Ver-)

http://youtu.be/aCOyq4YzBtY

Actually we can calculate the bending of photon using newtonian mechanics assuming it has a mass given by

m = E/c^2 = h \nu/c^2

The answer we get is exactly half of what GR predicts. You can find the this problem done in this book

http://www.amazon.com/Gravity-Introduction-Einsteins-General-Relativity/dp/0805386629

Anyone interested in this should read The Selfish Gene

You should read Sex at Dawn. It is a pop-sci book about sex in pre-agricultural societies (and how it operated nothing like most people imagine it did).

The book he wrote discussing his work on phantom limb sensations is called 'Phantoms in the Brain: Probing the Mysteries of the Human Mind'. I found the experiments and really the whole book fascinating.

The Mirror Box, at least to me, shows how bizarre and flexible the human brain can be while also showing a relatively simple hack that can help reduce the pain and unpleasant sensations from a phantom limb.

Edit: modified some wording