Universe Definition and 1000 Threads

In my fictional universe, I have several reaches and transformations and whatnot. Each power level is determined by the average power of a human. Humans are usually in a power scale of 1-5. This means that someone can be 5 times the strength of someone at maximum. Now. I need to figure out...

I understand that some old Machian interpretations of inertia require a closed universe. Now that it has been confirmed that the universe is expanding forever and is not closed, how does Machian explanations of inertia fit in with this?

Hello, I'm a sci-fi author and need to plot a course with distances and galaxy (cluster and super cluster) stop overs between the Coma Wall, Earth and the Great Attractor. I've looked at a few online 3D universe maps and 2D maps but have not found anything ideal. Any suggestions? Thanks so...

http://www.ox.ac.uk/news/science-blog/universe-expanding-accelerating-rate-%E2%80%93-or-it Now, a team of scientists led by Professor Subir Sarkar of Oxford University's Department of Physics has cast doubt on this standard cosmological concept. Making use of a vastly increased data set – a...

In the beginning of the universe, the hot matter of the entire universe was confined to a small volume. I would guess that compared to our time frame, time flowed slower than it does now. I would also guess that time has gradually slowed down since then. Is this significant in predicting the...

Hello. So the last few days there have been articles about how our universe may now contain around 2 trillion galaxies, up from 100-200 billion galaxies that was previously determined. But unfortunately I can't make complete sense of the articles I've read, including the one on NASA's site...

I learned about entropy is chemistry, can someone please explain how this term is used in physics? Thanks.

I was reading about the first few Planck seconds and noticed no mention of general relativity other than the horizon problem. I some googling and only came up with some 1979 research that took the assumption that gravity was less powerful in the past, which I find suspect and Was developed...

If space is expanding wouldn't that violate the first law of thermodynamics

One more question: it appears that portions of the universe are expanding away from us faster than the speed of light. Given this, particles in two 'parts' of the universe that are no longer causally connected should not be able to influence each other (due to speed of light constraint). So...

Hello. First of all, I must say that I'm new to this forum, so I apologize if I'm posting in the wrong section. I'm a 17 year old with not that much knowledge about physics, so if what I'm talking about makes no sense or is completely stupid, just let me know. A couple of days ago I asked...

How close to the speed of light would you have to travel to be able to traverse the entire span of the known universe(94 billion light years i think?) in a persons 80 year lifetime?

I was watching a documentary about dark matter and dark energy (actually a couple of them) and how this is pushing the universe apart. I tried to find answers on if something could be pulling our universe apart rather than pushing. I couldn't find enything on this, but maybe someone here could...

After Dark Energy will tear our Universe apart, every Hubble sphere would contain only 1 or 0 gravitationally bound structures. What is an average size of such structures? (As I understand, galaxy clusters are the "seeds" of such remnants?)

...and what is the difference between true 4D and the minkowski space? To me, it would be much easier to see universe as a 4D and us humans just experiencing the dimension of time differently. In my mind i pictured the universe as a complete 4D structure which we humans experience in one...

Usually when gravitational lensing is discussed, the examples are those of matter bending spacetime into a positive curvature. https://commons.wikimedia.org/wiki/File:Gravitational_lens-full.jpg In these cases, distortion of light is clearly evident as images of galaxies from behind these...

The question here is simple; would the existence of virtual particles make the universe an open system? And if not, why? I thank all who consider this question for their time and would love to hear an answer.

We live in a world with 3 space dimension and 1 time dimension, and i saw a video how a universe would look like is their where n-space dimension but what would happen if their where 2 time dimensions?

Why do quantum fluctuations of fields arise at high energies and temperatures? What is the mathematical formulation of these quantum fluctuations? Why are the sizes of these quantum fluctuations approximately the Planck size?

If we ever fully understood quantum science and all there is to know about it, could one say we then fully understand the universe? Or, would we never know at which point we know all there is to know? Would you be comfortable in the belief or proof nothing more could be discovered--about...

I have been thinking at this for a couple of days now: why are stars grouped in the massive collections that we call galaxies? I can assume that in the very early Universe, matter was grouped in these areas, that matter interacted thus resulting in the formation of stars. Then, the...

If every particle of the Universe was made to occupy the state at which it was 2 years ago, would there be an action replay of events from (T-2) yrs to T ? Or would subsequent events be different ?:rolleyes:

Hello.. I'm writer of science fiction and I want to write something similar to the X-men Jean Grey who has telepathic and telekinesis powers. I'd like the book to sound good and technical. May I know what laws of physics would be broken for telepathy and telekinesis to exist? Should I mention...

I was watching a video on Elon Musk. I believe he is a smart guy and he certainly knows is stuff. However, he said something in this video which I was surprised about and I can't seem to corroborate with various Google searching. Someone asked him whether there was enough Lithium on Earth to...

how have we figured out plank length of the universe ?and know its that size ?

I read many times that the early universe was opaque foremost because of the scattering of photons off free electrons (Thomson scattering). Why is the scattering off free protons not equally important? Btw, the same they say about stars. Photons within stars need a very long time to get out of...

As I understand it, in string theory the constants of nature can taken on a huge different number of possible values and when the universe cools after the big bang these constants of nature get locked in as it were and become , well constants. My question is, what if we discard string theory -...

As I understand it, the Universe is red-shifted (emission spectra) from any point of reference looking outwards. The Universe is expanding, but is matter being created at the same rate ? Does this mean that the density of matter in space is decreasing ? (density = mass / volume). What does this...

How can the universe be infinite and yet have a finite age?

What would the Earth's night sky look like? Would our eyes see any dark spots? Is there are way to calculate such a probability? This hypothetical is about the observable universe only. 93 billion light-years diameter, isotropic, visible light. Not sure what's the most appropriate tag for this...

My understanding is that matter tends to converge and form stars and in those stars fusion creates heavier atoms from lighter atoms, and this process repeats continuously. if this is true wouldn't it imply that throughout these star cycles the average atomic mass will just increase, and as the...

Guys, what do you think is beyond the edge of the universe? There are a lot of theories, and I believe that the universe expands the same speed as light because if it goes any slower, it would meet. I think light interacts with dark matter to form a "boundary" of the universe in form of pure...

http://www.iflscience.com/space/the-edge-of-the-universe-is-closer-than-scientists-previously-thought/ Hey, guys! I'm new in this forum and I found this interesting article. Damian

Just like to get an idea of what people currently think what the shape of the universe is. Since the curvature is likely zero, does this mean that the universe is infinite. Also, I get the idea that the size of the universe, if has one, extends beyond the light cone. How is this possible?

When the observable universe was the size of a baseball, did its gravity (field?) extend to (as opposed to towards) infinity?

I would like to imagine how would physics look in a Universe governed by Standard model, sans Higgs. IOW: how would the unbroken SU(2)*U(1) be different from our usual broken one? Matt Strassler has a similar article here...

Comic book physics question: Vibranium (a metal which exists only in the Marvel Universe) possesses "the ability to absorb all vibrations in the vicinity as well as kinetic energy directed at it. The energy absorbed is stored within the bonds between the molecules that make up the substance. As...

Near a black hole spacetime gets contracted, more and more as we get closer to it. At the event horizon the contraction (pull of spacetime towards the singularity) equals the speed of light, we could say that space is falling into the black hole at precisely the same rate as light trying to...

Including dark matter but not including dark energy, what's the Schwarzschild radius of the known universe? Actually, let me put it another way. What's the SR of all the matter and energy thought to be created at the Big Bang? So that would include not just all the matter we see but also all the...

Hi My academic background is in philosophy, and I know very little physics. My attraction to the principle of sufficient reason motivates my question. My understanding of one theory of the origin of the universe is that it started with a "singularity" which then exploded into our universe. It...

Experimental violations of Bell's inequality (Alain Aspect, et al) proved beyond a shadow of doubt that local hidden variables do not exist. However, in a 1985 BBC interview, John S. Bell said there was one loophole in those experiments that would allow for determinism: non-local hidden...

I would like to study more about the notion of time in modern physics. In particular, I would like to understand better the following question: how does one measure the time in the early universe? To measure time one needs to have clocks. A natural choice to be used as clocks would be particles...

The Dalton's atomic theory states that atoms can neither be created nor destroyed. Then how was the first even atom created in this blank space? Is it physically possible to create an atom?

[Sorry for the vague title, had a limit.] I have a question given in my Astronomy class: Below is a list of possible ways in which the universe could have been different. Some of these changes would make life as we know it impossible in our universe. Tick the boxes next to all the changes that...

We live in an expanding universe (at least in our epoch) so radiating sources in the cosmos look redshifted, the more the farther they are from us, with the limit being the CMBR which is redshifted to 3ºK when it was actually around 3000ºK when emitted. Were we to live in a contracting...

I just learned from an Astronomy course that when the sub atomic particles were not bound together, they were moving around freely, but after the universe expanded and cooled, they began to combine to form Hydrogen atoms. Now, before this combination period, the photons couldn't pass through...

There are links in the article to more science-oriented reports. http://www.csmonitor.com/Science/2016/0715/Scientists-create-huge-3-D-map-of-universe-validating-Einstein-s-theories That would be a great use for some of those Virtual Reality goggles.

(Sorry for my poor English.) I was watching a PBS video on expansion of the universe and the guy says the wavelength of a photon emitted in a supernova becomes larger as it travels to the Earth. Is it because the photon lose energy (to space)? If so, is that energy contributing to the expansion...

I've recently read that the universe is now estimated to be about 95 billion light years in diameter. This was based on what we now can observe (Hubble Deep Field for example), what is estimated to be seen with new technology (James Webb) and an estimate of what's beyond that which we can't yet...

The universe- from our understanding, is expanding, thus the regions (for lack of a better word) particles have not yet reached do not exist. How far our universe can/ will expand is unknown, it may be infinite, but we can conclude at this time, as it is still expanding, that it is finite. True...