Questions tagged [cosmology]
The cosmology tag has no usage guidance.
32
questions
2
votes
0
answers
240
views
Did Wheeler and Feynman said that vacuum zero point energy could boil the oceans?
Following on this Were Feynman diagrams motivated by the cosmological constant problem? and this Who was the first to estimate the vacuum energy discrepancy by 120 orders of magnitude? I found a ...
- 2,688
3
votes
1
answer
119
views
Were Feynman diagrams motivated by the cosmological constant problem?
Sean Carroll, while speaking about the history of quantum field theory, has said a couple of times (without being completely sure of its factuality) that Richard Feynman was motivated by his trying to ...
- 2,688
5
votes
0
answers
192
views
Who was the first to estimate the vacuum energy discrepancy by 120 orders of magnitude?
Apparently, this discrepancy is one of the "worst predictions" in the history of science. Clearly the vacuum energy calculation depends on many approximations and it is not clear how it ...
- 2,688
1
vote
0
answers
67
views
Who actually invented the Big Bang theory?
The Big Bang theory is famously attributed to Lemaître .
In a moment of rare sentience, I decided to consult Georges Lemaître's works to find out what the original Big Bang theory looked like. After a ...
- 409
1
vote
1
answer
80
views
+50
Views of stellar energy before fusion
Before there was an understanding of nuclear fusion, what hypotheses were there about the source of stellar energy? What methods, if any, were suggested for testing the hypotheses; alternatively, how ...
- 145
3
votes
1
answer
368
views
Why was Principia Proposition 43, Theorem 22 not published?
Why was Proposition 43, Theorem 22, of Newton's Principia not printed?
Weinberg, To Explain the World (2015) describes this proposition:
In an unpublished “Proposition 43” that did not make it into ...
- 5,229
2
votes
0
answers
71
views
Who coined the name "cosmological constant"?
I am aware that Albert Einstein first added the $\Lambda$-term to his field equations in his 1917 paper "Cosmological considerations in the general theory of relativity" (german: "...
- 129
2
votes
1
answer
380
views
How did they know that the space could expand?
The theory of general relativity was formulated around 1915 which could be summed up in words of John Wheeler, "Space-time tells matter how to move; matter tells space-time how to curve".
At ...
- 377
16
votes
3
answers
3k
views
What was the Big Bang model originally called?
The name "Big Bang theory" was coined by Sir Fred Hoyle. What did scientists originally call the Big Bang model?
- 261
0
votes
0
answers
31
views
Is there a synthetic chart of modern cosmology, showing the dependencies between measurements and laws?
I'm trying to figure out what are the different paths to indirect measurement of things that are out of experimenter reach; for instance, the age of the observable universe, or an estimation of the ...
- 101
0
votes
2
answers
131
views
Which modern sciences/technologies were contingent on the Copernican Revolution, & which could have developed even while believing in geocentrism? [closed]
Suppose that, for whatever reason, neither Copernicus nor anyone else had discovered the heliocentric model, and cosmology remained stuck in the geocentric model. ("For whatever reason" ...
- 11
1
vote
0
answers
46
views
Has someone ever proposed a "many worlds/histories" model where all possible boundary conditions are considered? [closed]
The Hawking-Hartle no boundary condition is a well known model that tries to explain how did the universe begin. The authors considered a "many worlds/histories" model considering a sum over ...
- 297
0
votes
0
answers
51
views
How do the latest measurements of the Hubble expansion match the QFT prediction?
From what I read the expansion of the universe predicted by QFT is said to be the worst theoretical prediction in the history of physics.
There is also lots of buzz in the astronomy press about the ...
- 1,223
5
votes
1
answer
404
views
Early geographically accurate drawings of Earth
The first, known to me, drawing of a simulated view of Earth from outside—roughly passable* by modern standards—is this pic from 1834 attributed to Henry De la Beche
(source: abroadintheyard.com)
Was ...
- 159
2
votes
2
answers
232
views
Was Fred Hoyle’s career due, in part, to the popularity of the static universe in 1950s?
Watching the video So much universe, so little time, I was surprised to hear Fred Hoyle talked about in glowing terms.
According to the narrator, by the late 1950’s the big bang model was losing ...
- 6,689
6
votes
1
answer
115
views
Why is it that so many early astronomers and cosmologists wanted to believe in a static/infinite/eternal Universe?
I've been doing some research for a cosmology series and I'm struck by how many physicists and philosophers, from Newton to Einstein, had a notion that the Universe should be static and eternal. Why ...
- 61
0
votes
0
answers
41
views
Did pre-Galilean astronomy inspire Mach's principle?
Was Mach, in his formulation of "Mach's principle," influenced by pre-Galilean astronomy, such as that of Aristotle in On the Heavens, where heavenly bodies influence terrestrial ones?
- 5,229
1
vote
2
answers
301
views
What is the ancient cosmic canon of proportion and its role in the history of science?
Who had direct inside knowledge of the canon through the alleged secret oral tradition? Some possible examples that have been alluded to include Pythagoras, Plato, Euclid, Copernicus, Galileo, Kepler, ...
2
votes
0
answers
105
views
Thomas Kuhn and the Relationship between Astronomy and Cosmology
In The Copernican Revolution, Thomas Kuhn states that "...only the Western civilizations which descend from Hellenic Greece have paid much attention to the appearance of the heavens in arriving at [...
- 121
4
votes
0
answers
150
views
Did Paul Dirac believe in multiple universes?
Prominent physicist Paul Dirac proposed a hypothesis that said that constants and laws of physics would evolve with time into different constants and laws of nature.
This hypothesis was used by ...
- 81
1
vote
0
answers
175
views
Did Werner Heisenberg ever agree or propose the existence of some kind of multiverse?
I was watching a video (https://www.youtube.com/watch?v=muJYTeQlvC4) where the director of a videogame company speaks about one of its most successful games. This game is set in a floating city which ...
- 81
2
votes
0
answers
93
views
Did Wheeler ever propose the existence of a multiverse containing parallel simultaneous universes?
It is known that the physicist John Archibald Wheeler proposed the existence of a multiverse in the form of a set of cycles of Big Bangs and Big Crunches (Cyclic/Oscillatory Multiverse Model).
But I ...
- 81
2
votes
1
answer
242
views
Are Wheeler's It from Bit/Participatory Universe and the Multiverse related?
Could I ask you for the relation between Wheeler's ideas and the multiverse? Do you know if these are related?
I ask you this because I found this very interesting article written by Kip Thorne with ...
- 21
0
votes
0
answers
348
views
Is there any historical mention of Richard Feynman being aware of multiverse theories of cosmology?
The reason I ask is because he talks about the fine structure constant in one of his undergraduate lectures.
The reference to its mystery is analogous to all the special constants of nature such as ...
- 1,223
10
votes
1
answer
7k
views
What equation is Stephen Hawking most noted for?
I am trying to equate the famous Stephen Hawking to some of our other famous scientists and noted that the vast majority have an associated equation with their name. As for example Einstein was the ...
- 1,223
5
votes
3
answers
370
views
Was an expanding universe proposed before Edwin Hubble's observations?
General relativity (1915), as I've heard it explained, describes a universe that is either shrinking or expanding. By adding a cosmological constant it can describe a universe in eternal steady state, ...
- 498
6
votes
1
answer
481
views
When did the estimates of planetary distances made between Ptolemy and Copernicus produce the pattern suggesting heliocentrism?
Two patterns in the structure of the Ptolemaic model make the transformation of coordinates to the Copernican model seem "natural" to modern eyes:
the alignment of the radii of the (second) ...
- 213
6
votes
3
answers
426
views
Nowadays I see a distinct "line" dividing people working in Mathematics and the Physical Sciences. Why?
The direction in which leading research is heading in these subjects (Math, Physics) is very much different and don't seem to be in tandem. Is this something that developed in more recent times? This ...
- 99
6
votes
1
answer
390
views
Who discovered that the radius of the observable Universe is 46 billion ly?
I know that before the beginning of the 20th century it was thought that the Milky Way galaxy was the whole universe. Then there was the discovery of galaxy redshift, and the size of the Universe was ...
- 281
3
votes
1
answer
86
views
Who introduced the notion of comoving distance in cosmology?
According to Wikipedia:
Comoving distance factors out the expansion of the universe, giving a distance that does not change in time due to the expansion of space (though this may change due to ...
- 281
5
votes
0
answers
84
views
Did breaking of discrete symmetries play a role in the development of steady-state cosmology?
If you look at the original pair of 1948 papers[Bondi 1948,Hoyle 1948] that proposed the steady-state model, it's clear that they knew they were throwing out a lot of cherished principles of physics. ...
user466
7
votes
1
answer
286
views
What is the origin of the term recombination?
During the introductory lecture to a cosmology course I'm currently taking, there was a brief discussion of some of the "highlights" of the Big Bang model. One of these is, of course, recombination. ...
Danu♦
- 3,812