History Definition and 555 Threads

I know that QM and GR have not net been combined, so perhaps this is a foolish question, but I'll try anyhow. A photon traveling in the vacuum, has energy h/λ. That energy is fixed. It never varies in any circumstances (true?) except one. That one is the expansion of space time; i.e. the...

I would be interested in the equations of a gyrostatic ether as brought up by McCullach and Lord Kelvin, best in a modern notation. Before people jump on me: I an not interested in questioning modern theories like SR but rather in the extensions of continuum mechanics these theories go in hand with.

Abul-Walid Mohammed ibn-Ahmad Ibn-Mohammed ibn-Roshd this historical character is admitted as a lawyer but I do not think that there was job as lawyer in his time.

Of diseases discovered in the last 50 years, which of them currently has the highest incidence in the developed world, and what is that percentage ? ADHD is allegedly affecting over 5% of children in the developed world ... http://ajp.psychiatryonline.org/article.aspx?articleid=98517 To me...

I'm trying to create a chronological timeline of the formation of solids in the solar system with examples of meteorites for each step. Let me know if this order looks right. First solids condense in the solar nebula (Calcium aluminum inclusions in carbonaceous chrondrites). Chondrules rapidly...

Just been looking around for any good resources or databases which show history of stars in the universe. I have mostly been looking into the size and chemical content of them (like those of population I, II, III). But just looking for some real data and numbers to go with it, like star sizes...

Good to see mathematics hitting the headlines this morning, with news of the first-ever female Fields medallist.

Here is a fun talk by Fay Dowker on a path integral approach to the Greenberger-Horne-Zeilinger (GHZ) correlations. It's a physical instantiation of N. David Mermin's "no instruction sets" for GHZ in his Am. J. Phys. paper "Quantum mysteries revisited," v58, Aug 1990, 731-734. The talk...

In chapter 2.2 of Feynman's book on QFT, he states that the probability amplitude of a particle going from a to b is the sum of contributions from all paths, and that each path contributes the same amplitude, but with a different phase. My question is, why does Feynman state that this is the...

As I wrote above, together with mathematics, historical analysis has always been a passion of mine and when possible I have tried to combine the two. Recently, while I'm writing a historical text about the First World War, I had to deal with one of the most complex events of the nineteenth...

This has been bugging me for a year or so - sorry if this is off topic, but would anyone on the forum be able to name a book on atomic physics I read as a child? It was a non-fiction, illustrated picture book I read as in the late 70's or very early 80's, giving the history of atomic science...

Not sure if this has been posted about already, but I enjoyed this :). (Although I agree with Newton- I have no idea why they paired him up with Bill Nye...) This one's good too

Interesting Hist Channel show on Star Trek and Physics: https://www.youtube.com/watch?v=vNiDoT7blX8 Of particular interest is the number of scientists who were influenced by Star Trek in their youth.

A very good article I came across. Worth reading, and then we know why the US is where the US is.. http://www.ams.sunysb.edu/~tucker/monthlytucker.pdf

Hey everyone, I am pursuing my undergraduate studies in Physics.I found the overall syllabus very messy and disordered,so I connect all the dots ,I am searching for books for background reading related to Physics.Are there any books available on 'History of Physics' ?

I'm quite interested in the history behind vector analysis especially Curl and Divergence and gradient operators etc. When James Maxwell derived Maxwell's equations of electromagnetism where these sorts of operations well known and commonly used, or are they modern fabrications. Did Maxwell...

Stop by every day to see a fun historical science fact for that day.

Hello! Could you, please, name some(if any exists) good reviews about building the general relativity? In all details: with attempts of building the vector theory of gravitation by Poincare; with long Einstein's efforts of building the scalar version; with prediction some of the effects, like...

I would really like to get a good understanding of how modern algebra developed, especially ring theory. Two books I have recently bought are as follows: Modern Algebra and the Rise of Mathematical Structures by Leo Corry. and Episodes in the History of Modern Algebra (1800 - 1950) by Jeremy...

Can someone please help me with the following: Prove that if the sum of two consecutive intergers is a square than the square of the larger integer will equal the sum of the nonzero squares. Hint: if n+(n-1) = h^2 then h is odd. Not really sure where to start. Thanks in advance

In this article from City Journal, the writer Heather MacDonald states the following: "The American Founders drew on an astonishingly wide range of historical sources and an appropriately jaundiced view of human nature to craft the world's most stable and free republic. They invoked lessons...

The history of mathematics...help with resources Hey guys I need help finding good resources to help me understand basic to advance math from a developmental point of view, the applied necessities of the inventors of math operations and concepts. For example the addition operation was...

I don't know if such thread has been created, all I can find out is one mentioning Zhang's initial bound of $7 \times 10^7$. This has been greatly improved by now so I thought it is worthwhile to post it here as well as the resources which I somehow collected from here and there. History; a...

Interesting take on solving the Squaring the Circle problem enshrined in law: http://pulse.edf.com/en/day-pi-became-3-2-instead-3-14159/?utm_source=OutbrainInter&utm_medium=cpc&utm_campaign=Trafic

This horse has been beaten so many times, it's not funny. But I, like everyone else need words of advice from people that aren't going to tell me what I want to hear (or maybe they will). Anyway, I messed around a lot after high school, took numerous classes at various community colleges...

Non-maths general question on history of space time :) Hello, I'm doing a Bsc project on space-time and was hoping to receive some advice on how others would structure the history of the topic. I know this is a broad question but what I'm struggling with is how to narrow down the relevant...

Hello! I've recently begun to read a lot of nonfiction books. I'm currently reading a book about stories told by Richard Feynman about his amazing life. It's hilarious and so clever. I would absolutely LOVE to read a book on the history of physics! I think it's really fascinating. Could...

I do not have the best GCSE's, no-ones fault but my own, I slacked and daydreamed a lot where I even had to go to the hospital to see if something was "wrong". I made it up via BTEC and got DD, could of been an extra D but through choosing an apprenticeship, I had to sacrifice the extended...

Hi Im new here, and have begun to read this book. I don't have any science qualification but I've read a few books on evolution. I'm making notes as I go along and here are 2 difficulties I have. 1) It says gravity is for large scale and quantum is at the small scale. I am just wondering...

http://news.discovery.com/tech/videos/be-afraid-atlas-robot-unveiled-video.htm Their video page. I thought it was TMZ at first.

Let's say you wanted to determine what day in a certain amount of time had been the most influential in our lives today. I theorized that whatever the time period, the first day in that time period would automatically be the most influential day. I though this because as you go farther back in...

So my physics teacher assigned us with this task (title). Basically our objective is to compose a short narrative written in the pov of an electron. The story has to center around places that an electron visits, that once lived in an atom wool, and ultimately entered the ground. The electron has...

For some reason I thought it would be easy to find but I'm trying to find a history of the integral. I'm not really looking for Wikipedia because I know that anyone with a computer can go and change the content so I'm not sure how true it is. Does anyone know of a good source I can look at...

This was described by Michael E. Mann,professor of meteorology at Penn State University. http://www.meteo.psu.edu/holocene/public_html/Mann/news/interviews.php Others have had readings that give similar results. "While scientists and environmentalists have used the daily milestone to...

History Channel's "Ancient Aliens" I watched a few episodes of this after repeated requests from my friends ,i not really convinced by their theories but since my knowledge of physics is limited ,i might need some help in either dismissing or accepting their theories, i hope those who are...

http://arxiv.org/pdf/1304.3724.pdf I thought this paper worthy of a read

I'm curious about two things. Why did Einstein's 1905 paper contain no citations? Nowadays most papers have one or two pages full of citations, I don't know about back then but he must have had a few. Secondly, Einstein willed some of his Nobel money to his wife Maric. But that was a year or...

I'm interested in the history tables other PF members are getting as they try out Jorrie's online tabulator. What's your current favorite? So this is to invite folks to use the LaTex feature to get a version of your table you can print in a post in this thread. Which values of the Hubbletimes do...

I've only got a layman understanding of this. Why did Planck find quantization necessary and how did he come up with the equation E = hf?

I ask this because of the lack of actual credible History programming, a lot of the programming now is either reality television or pseudoscience nonsense. http://www.history.com/schedule

I was watching Lincoln last night, and at a part were the idea of women voting was laughed at by the legislators. My mom's comment was along the lines of "Oh right, women weren't smart enough to vote back then." or something similar (and a sarcastic tone of course). My retort was that around...

Here's a sample history from fairly far back in the past, going up to the present (S = 1) in 20 expansion ratio steps, and then in another 20 expansion steps, going out a good stretch into the future, when distances will be 25 times what they are today. I could have asked for a wider expanse of...

What is its importance? Where there any publications to prove exactly the formulation of Klein Nishina formula of Compton Effect? Why is it that complicated to prove..

I would like to know the history of the value of the speed of the expansion of the universe. If today it's 74.3 ± 2.1 kilometres per second per megaparsec then how much it was a billion years ago, 5 billion years ago, 10 billion years ago, and how much it was in the first million years after...

Hi PF members! I've recently been working on an image (see attached thumbnail) in which I try to include the most important/influential steps in the history of science. Now, I am very well aware that this is not easy (!) :smile:, and it will always be debatable and not without controversy...

Okay so I'm using ncbi and when using the nucleotide database, when I access the revision history of a result of any query, I get a lot of sequences. Surprisingly they all are of the same version. Why? If each is different shouldn't they have different version numbers? They all have different...

I learned on the textbook that human calculated the orbital of planets that near the Earth first then based on the difference of the actual data of the planet orbitaland that of human predicted, human calculated out other planets' orbital and predicted some planets like Neptune and Pluto. I...

The credentials and employment history of Thomas Campbell, author of "My Big TOE". Hello guys. I am currently embroiled in writing a paper on the limitations of the standard scientific method and wish to reference Thomas Campbell's work in said paper. On his website, and during interviews and...

The other night I was contemplating my own mortality, as you do, and became rather depressed by the thought that in two or three generations after my death I'll be forgotten, after a couple of large perspective modifiers, I came to the conclusion that I'm in the same boat as the vast majority...

Calling math history geeks -- any reading suggestions? Hey everyone! Inquiring minds (well, at least one) want to know: what are some good books on math from a historical perspective? I recently acquired "Mathematics of Nonmathematicians" (Dover Books) as the reviews suggested it was mostly...