Star explodes halfway across the universe

[Abstract]

The "Space" you're thinking of, and the "space" that's beyond our universe is likely far different. We just defined the black emptiness that's outside our planet as "Space". We consider it a vacuum, but it really depends on scale and perspective. I don't know how to explain it, but it just ended up as our baseline, and a rather arbitrary one.

Imagine sprinkling beach-sand onto a piece of white paper. Imagine that the paper was the universe, and the sand was all the "stuff" in our universe. I guess if you were much larger, and capable of holding onto the universe with two hands as though the Universe was a sheet of paper, all the dark empty "Space" we see may not appear so great. However, from the point of view of a microscopic organism, DAMN that's a lot of empty space between grains of sand!! We already know how small we are on the grand scheme of things. We just need to gain some perspective of this.

 

[Prof.]

Where the hell is Michio Kaku when you need him?

^ Coolest theoretical physicist EVER!!!

Oh! we can't forget about Astrophysicist Neil deGrasse Tyson

 

[d_and_n5000]

The "Space" you're thinking of, and the "space" that's beyond our universe is likely far different. We just defined the black emptiness that's outside our planet as "Space". We consider it a vacuum, but it really depends on scale and perspective. I don't know how to explain it, but it just ended up as our baseline, and a rather arbitrary one.

Imagine sprinkling beach-sand onto a piece of white paper. Imagine that the paper was the universe, and the sand was all the "stuff" in our universe. I guess if you were much larger, and capable of holding onto the universe with two hands as though the Universe was a sheet of paper, all the dark empty "Space" we see may not appear so great. However, from the point of view of a microscopic organism, DAMN that's a lot of empty space between grains of sand!! We already know how small we are on the grand scheme of things. We just need to gain some perspective of this.

That's an interesting way of putting it. That makes quite a lot of sense.

 

[Gelfin]

Sorry, but how can anyone state categorically that the universe is or is not finite? Being a regular on MacRumors does not empower your words nor diminish how silly you sound.

*shrug* As I said, not my field, and the people I have known in the field rapidly get over my head when I talk to them about it.

However, after looking around a bit, I found something relevant. The NASA WMAP mission site has a very accessible tutorial section describing roughly how people go about knowing the sorts of things we're talking about here.

Second, though, it appears that the closed space-time model I was describing in my previous post is pretty well off the table according to the latest (this month) results from the experiment. So that previous post? Yeah, forget it. It was popular theory that, according to the latest results, just isn't the case.

"We now know that the universe is flat with only a 2% margin of error." According to other information on the WMAP site, that would mean an infinite Universe bounded only by the Big Bang. All we can talk about is what we can see, about 13.7 billion light years in all directions, and whatever if anything might be beyond that is just beyond our ability to talk about sensibly.

 

[AustinD]

The idea of Infinity is something that can easily keep you awake, because can something that is infinite have a beginning?

A geometrical ray is infinitely long but has a beginning? My old geometry teacher had a riddle type thing that he told us in the very first week of school and kept the answer until the end of the year:
If an infinitely long rope goes into an infinitely deep hole, what happens?
ANSWER: " The rope will break from its own weight dangling in the hole."
I was very disappointed he kept us waiting a year for that.

 

[GimmeSlack12]

All I know is there is A LOT of stuff out there. Get this there is something referred to as 'The Great Attractor' that is so big (and mysterious) that it is pulling our Galaxy as well as all galaxies in our region towards it.
http://en.wikipedia.org/wiki/Great_Attractor

Blows my mind that there is this giant 'thing' out there that has so much Mass it is pulling an entire region of space towards it. Incredible.

 

[nickster9224]

So a star explodes in space, does anyone hear it?

 

[EricNau]

It's not infinite but it is increasing in size everyday - faster and faster.

Actually, the rate at which the universe expands does not vary; only the rate at which objects appear to move away from us is getting faster and faster, due to the fact that an increasing amount of space between us and any given object is increasing, which leads to increasingly faster speed of expansion. In other words, since space itself is increasing, the more space between two objects, the faster those two objects move away from each other. Essentially, more space = more speed.

This constant speed of expansion is known as Hubble's Constant (or Law), which states that the redshift in light (i.e. speed) of distant galaxies is proportional to their distance.

you mean the mass is expanding faster and faster

the space is already there lol

No, he's correct. The space of the universe is expanding.

 

[scotthayes]

Not a good idea to read this thread from start to finish at 6:30 in the morning. My head really hurts now.

 

[OnlyMarcusCannn]

Here's an interesting scenario: Let's say there is, in fact, an "end" to the universe. We have the technology to make a space ship to reach that far (haha). Once reaching the end, would the space ship just, uh, stop? What could possibly be beyond the universe? Can one even answer these questions? Sheesh, mind boggling indeed.

 

[CorvusCamenarum]

Here's an interesting scenario: Let's say there is, in fact, an "end" to the universe. We have the technology to make a space ship to reach that far (haha). Once reaching the end, would the space ship just, uh, stop? What could possibly be beyond the universe? Can one even answer these questions? Sheesh, mind boggling indeed.

But there is an end to the universe. There's a restaurant located there.

 

[dukebound85]

Actually, the rate at which the universe expands does not vary; only the rate at which objects appear to move away from us is getting faster and faster, due to the fact that an increasing amount of space between us and any given object is increasing, which leads to increasingly faster speed of expansion. In other words, since space itself is increasing, the more space between two objects, the faster those two objects move away from each other. Essentially, more space = more speed.

This constant speed of expansion is known as Hubble's Constant (or Law), which states that the redshift in light (i.e. speed) of distant galaxies is proportional to their distance.


No, he's correct. The space of the universe is expanding.

ok then whats on the other side of the space? i dont think anyone can be so definitive about this topic to be honest

 

[EricNau]

ok then whats on the other side of the space? i dont think anyone can be so definitive about this topic to be honest

Quite simply, there isn't anything (that we know of) outside of our universe. Since "space" was created with the Big Bang, space as we know it only exists within our universe.

Once you start addressing things outside of our universe, you leave the world of science.

 

[Prof.]

Some scientists suggest that there is an oposite (alternative) universe outside our own. This universe, instead of containing matter, would theoretically contain ANTI-matter*. However, this is just pure theory and has never been proven.

*Anti-matter is the opposite of matter (the stuff in which our universe is made up of) and a gram of anti-matter, when introduced to matter, would theoretically destory a large area the size of New York City.

SOURCE: "The Universe" on The History Channel

 

[clayj]

How to Prove the Universe is not Infinite in Size

Look up at the sky at night. What do you see?

That's right, blackness. That the sky is black at night demonstrates that the Universe is not infinite in size. If it were, then every conceivable sightline in the sky would terminate on the surface of a star. Since stars emit light, the entire sky would be white with starlight in any direction you looked. That this is not the case demonstrates that there are a finite number of stars and that the Universe is finite in size.

And while the volume enclosed by the Universe is rapidly expanding, the mass inside is not expanding at all. This means that over the billions and trillions of years to follow, we can expect things to get further and further apart from each other... stars to die for good or collapse into or be swallowed by black holes... and for things to get VERY cold.

Entropy sucks, but you can't escape it.

 

[yg17]

The massive scale of the universe is just something you can never get your head around. This event happened 7.5 BILLION years ago and we're just now seeing it....that's insane when you think about it.



Next time someone calls us IT guys at work complaining that their internet is slow, I'm going to tell them that it could be much worse, and it could take 7.5 billion years for their data to reach them

There are theories that other universes (possibly with different laws of physics) are floating around, hitting into each other, creating little and big bangs all the time, some of which create new universes.

Kinda like humans...you know, the hitting on each other, some banging, and then new humans are created

 

[EricNau]

Some scientists suggest that there is an oposite (alternative) universe outside our own. This universe, instead of containing matter, would theoretically contain ANTI-matter*. However, this is just pure theory and has never been proven.

Technically, it's less than a theory or even a hypothesis, as there is currently no means to either contradict or support such a notion.

Like I said before, once we start talking about things outside our universe we leave science behind and we're left with nothing but pure speculation.

 

[Prof.]

Technically, it's less than a theory or even a hypothesis, as there is currently no means to either contradict or support such a notion.

Like I said before, once we start talking about things outside our universe we leave science behind and we're left with nothing but pure speculation.

The word 'hypotheses' is defined as 'a mere assumption or guess.' So techniqually, it is a hypotheses.

 

[EricNau]

The word 'hypotheses' is defined as 'a mere assumption or guess.' So techniqually, it is a hypotheses.

According to the Oxford English Dictionary, a hypothesis is "a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation," based upon the greek word hupothesis meaning 'foundation.'

Furthermore, the scientific method, as originally put forth Sir Francis Bacon in the seventeenth century requires that one can test a hypothesis (i.e. it must be Falsifiable).

Unfortunately, the very nature of science does not allow us to scientifically address concepts outside our universe.

 

[GimmeSlack12]

Aside from the definition of Hypothesis the existence of anti-matter is already a known fact and it exists in our everyday world. For all sub-atomic particles (muons, pions, gluons, etc.) there exists an anti-particle (anti-matter) that is the opposite in charge of it's real matter component. When an anti-matter and matter particle collide they annihilate each particle and produce a photon. Light.
Anti-particles also exist in other natural reactions (i.e. Beta decay).

Outside of the Universe, as far as I know, there aren't any leading thoughts on if there even "is" an outside the Universe. As Psycho had mentioned there are thoughts on 'membranes' or 'branes' that when they collide the point of collision creates a new big bang, or Universe. This is all interesting but just way to abstract for me.

 

[JNB]

Outside of the Universe, as far as I know, there aren't any leading thoughts on if there even "is" an outside the Universe.

I guess that depends on what the definition of 'is' is...

 

[72930]

Outside of the Universe, as far as I know, there aren't any leading thoughts on if there even "is" an outside the Universe. As Psycho had mentioned there are thoughts on 'membranes' or 'branes' that when they collide the point of collision creates a new big bang, or Universe. This is all interesting but just way to abstract for me.

Horizon really clears up complicated ideas into a nice neat package to think about. If possible, I recommend anyone to get hold of their shows on 'The Universe'.

 

[Maui]

Look up at the sky at night. What do you see?

That's right, blackness. That the sky is black at night demonstrates that the Universe is not infinite in size. If it were, then every conceivable sightline in the sky would terminate on the surface of a star. Since stars emit light, the entire sky would be white with starlight in any direction you looked. That this is not the case demonstrates that there are a finite number of stars and that the Universe is finite in size.

Setting aside whether I agree with your conclusion or not ("finite" is not usually a term that is debated with respect to the "size" of the universe), but your conclusion does not follow from your statements for several reasons, including the existence of dark matter, the size of the universe itself, and the fact that most light reaching the Earth is blocked by the atmosphere.

 

[GimmeSlack12]

I guess that depends on what the definition of 'is' is...

According to the Oxford English Dictionary, is, can mean anything from "it just is" to "you don't understand what it is".
I seriously don't know what the hell I'm talking about.

 

[GimmeSlack12]

Setting aside whether I agree with your conclusion or not ("finite" is not usually a term that is debated with respect to the "size" of the universe), but your conclusion does not follow from your statements for several reasons, including the existence of dark matter, the size of the universe itself, and the fact that most light reaching the Earth is blocked by the atmosphere.

The philosophy that in an infinite universe you would have a sky full of light is correct. It doesn't sound right, but it is, and it is a prime example of how difficult it is to embrace "infinity". You have to think that the sky would be illuminated in all directions because there is something everywhere. There is nothing that hasn't been done infinite times. Example: Isaac Newton having an Apple fall from a tree and hit him on the head will happen an infinite number of times on an infinite number of identical planets that are infinitely named Earth. An infinite number of times this will happen, along with an infinite number of variations that will also occur infinite number of times.

Infinite is incredibly vast, it is truly "without limit" and this notion is not an easy one to understand.