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What if in 200 years data will show Andromeda slows down its approach with Milky Way?

It is possible too, right?

Milky Way will fly together with Andromeda toward common gravitational attractor.

a reply to: greenreflections

I don't know what would slow it down before the collision, when it should be speeding up. It will slow down after the two galaxies make their first pass.

When galaxies collide, it's not like two cars having a head on collision. Colliding galaxies do something like a "dance", and the future "dance" between Andromeda and the Milky way has been roughly illustrated in the following images. I posted this previously on ATS and saved the image but not the link so I forgot where it came from, but it was a decent source, though any sources making these predictions are making best guess simulations, partly because we don't have a good view of the other side of our galaxy (We actually have a better view of Andromeda):



Here's a good youtube video about the future collision with animations of what is expected to happen:

originally posted by: Arbitrageur
a reply to: greenreflections

I don't know what would slow it down before the collision, when it should be speeding up. It will slow down after the two galaxies make their first pass.

When galaxies collide, it's not like two cars having a head on collision. Colliding galaxies do something like a "dance", and the future "dance" between Andromeda and the Milky way has been roughly illustrated in the following images. I posted this previously on ATS and saved the image but not the link so I forgot where it came from, but it was a decent source, though any sources making these predictions are making best guess simulations, partly because we don't have a good view of the other side of our galaxy (We actually have a better view of Andromeda):

I know what it might mean galaxies collide. Milky Way actually has undergone collisions number of times before. Andromeda might pass through Milky Way undisturbed or just a little.

a reply to: Arbitrageur

interesting, thanks !

so what exactly is the universe expanding INTO ?

originally posted by: syrinx high priest
a reply to: Arbitrageur

interesting, thanks !

so what exactly is the universe expanding INTO ?

The size of the universe is either finite or infinite, we don't know which. If it's infinite the question doesn't make any sense, and if it's finite, we don't know and probably will never know because we can only see a portion of the universe called the observable universe which doesn't appear to contain any answer to that question.

originally posted by: Arbitrageur

originally posted by: syrinx high priest
a reply to: Arbitrageur

interesting, thanks !

so what exactly is the universe expanding INTO ?

The size of the universe is either finite or infinite, we don't know which. If it's infinite the question doesn't make any sense, and if it's finite, we don't know and probably will never know because we can only see a portion of the universe called the observable universe which doesn't appear to contain any answer to that question.

interesting, thanks

what came before the big bang ?

a reply to: syrinx high priest
Some physicists are actually trying to answer that difficult to answer question. There was a documentary explaining their progress on youtube which I posted here earlier but you missed the opportunity to watch it because now it's gone from youtube. No answers yet but instead of just shrugging and saying "who knows?" they came up with some different ideas that they are now trying to figure out how to test by comparison with observations. Some of the ideas involved the big bang theory not being completely correct. Apparently the ideas of a singularity in either the big bang or a black hole don't sit well with many physicists, so if they are not singularities, what exactly were/are they?

a reply to: Arbitrageur

Has anyone ever attempted to build a neutrino free vacuum?
What do you think, would happen inside one?

originally posted by: Peeple
Has anyone ever attempted to build a neutrino free vacuum?
What do you think, would happen inside one?

Most neutrinos go right through the Earth so if the entire Earth doesn't stop them and the Earth is pretty much all we have to work with at the moment, probably not. Actually we use the Earth to block other particles to make it easier to measure neutrinos inside the Earth.

If you wanted to block half the neutrinos, you'd need a light year thick lead shield. That's a mind-boggling amount of lead. Pluto is something like 5 light hours away and it took one of our fastest space ships over 9 years to get there. So that's not even one light day of the 365+ days in a light-year.

Since they don't have much mass and don't interact much, the only places we'd be likely to notice changes in neutrino populations would be in neutrino observatories.

a reply to: Arbitrageur

Doesn't that bother you, there is this massive amount of particles seemingly without a "job"?
That just doesn't sound like something the universe would do, does it?

originally posted by: Peeple
a reply to: Arbitrageur

Doesn't that bother you, there is this massive amount of particles seemingly without a "job"?
That just doesn't sound like something the universe would do, does it?

Nature seems to follow certain conservation laws we've observed, like conservation of mass/energy, conservation of charge, conservation of momentum, etc. I wouldn't have put it quite this way without your question, but in the context of your question neutrinos do have a "job" in these conservation laws.

For example take the decay of a neutron. Without the neutrino the decay would not follow nature's "conservation of Lepton Number" rule, so I suppose you could say the "job" of the neutrino is to make that decay follow nature's conservation law:

Conservation of Lepton Number

Nature has specific rules for particle interactions and decays, and these rules have been summarized in terms of conservation laws. One of the most important of these is the conservation of lepton number. This rule is a little more complicated than the conservation of baryon number because there is a separate requirement for each of the three sets of leptons, the electron, muon and tau and their associated neutrinos.

The first significant example was found in the decay of the neutron. When the decay of the neutron into a proton and an electron was observed, it did not fit the pattern of two-particle decay. That is, the electron emitted does not have a definite energy as is required by conservation of energy and momentum for a two-body decay. This implied the emission of a third particle, which we now identify as the electron antineutrino.

What would bother me more is if the hypothesized "WIMPs" which might make up dark matter don't interact with anything we know of, which is one possibility. However they would still have a "job", which would be to provide the dark matter mass which creates the structure of the universe, but I wouldn't like it if they are impossible to detect. However I'm convinced that Nature doesn't care at all what I would like or not like. My goal is to figure out how Nature really works, not say how I think it should work and then try to explain its function inside some box I've created. Nature doesn't care what we think so if it does have things without any "job" and that's the way it works, then we will just have to get over it.

originally posted by: syrinx high priest


its more a question of if light is sort of a particle and sort of a wave would it benefit from the momentum of the source of the light already being at light speed ?

could you see it in front of you ?

Like Arbitrageur mentioned there is no time flow at light speed. So if you could put your consciousness into a photon there would be no time for seeing things or having any experiences at all.

An interesting pdf of some free energy ideas using capacitors and back emf from a coil.


www.filedropper.com...

originally posted by: Peeple
a reply to: Arbitrageur

Doesn't that bother you, there is this massive amount of particles seemingly without a "job"?
That just doesn't sound like something the universe would do, does it?

Who knows? There's mosquitoes.

My analysis is that if there is a God, He can be a real dick at times.

a reply to: mbkennel

My idea behind that question was they could be "stem cell particles", as they are known to oscillate, travel super fast and time slows down at the approach of light speed, I was guessing they are something like the "energy and spin ambulances".

Taking in excess charge from other particles.

originally posted by: p75213
An interesting pdf of some free energy ideas using capacitors and back emf from a coil.

www.filedropper.com...

Free energy is a scam and so is the website you posted.

download.cnet.com...

"Complete Scam!"

originally posted by: Peeple
Taking in excess charge from other particles.

Neutrinos have no charge so they can't take any excess charge from other particles. In fact the word "neutrino" looks like sort of a variant of "neutral" as in no charge, doesn't it?

a reply to: Arbitrageur

Ah #! The neutron decays into a proton, right?
Okay but ahem excess mass? And ahem... just forget what I said...

originally posted by: Peeple
Ah #! The neutron decays into a proton, right?
Okay but ahem excess mass? And ahem... just forget what I said...

The neutron decay is described in the external source quoted in this post:

www.abovetopsecret.com...

Remember you were suggesting neutrinos had no "job" and I was trying to show that they sort of do have "jobs" of maintaining nature's conservation rules, at least that's one way of looking at it if you think they must have "jobs".

a reply to: joelr

Interestingly, at the largest scale, your question about the edges of the universe has a similar problem. Spacetime expands slowly on a local scale, like for galaxies and local clusters of galaxies. But galaxies really far away are moving away from us much faster..

But why do you think is that? Space-time expansion should not be different from where we are compare to the most outskirts of cosmos if we assume space-time expands equally from every point of it, imo.
Why space-time locally expands slower than we clock expanding distant galaxies especially when it is thought that expansion must be faster than light by now to accommodate calculations? The Moon should be getting further away from the Earth). Or, are there special areas of space-time where expansion more preferable?


thanks)



Reason: correction/ the Moon IS getting further away from the Earth/

any orbit calculation should give the rate of expansion. If space-time as a frame where everything happens has flexibility to it then correlation between two masses interaction should correspond to some even number that states cosmos expansion rate.

cheers))