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4
votes
2answers
102 views

Is there any proof of space being created?

Is there any proof for space being created? Because I guess an explanation for the dark energy (dark = our understanding of it) could be that there is a gigantic amount of matter/dark matter that we ...
0
votes
2answers
127 views

Are we made of stars we're seeing? [duplicate]

a fresh astronomy enthusiast here. Recently I've been reading upon how immensely far other stars are from our solar system and how is it possible that we may be seeing stars that are already dead. My ...
16
votes
4answers
1k views

Does matter accumulate just outside the event horizon of a black hole?

My understanding is that time slows and approaches stopping when approaching the event horizon of a black hole. I have seen this explained several places, including a brief explanation in the last ...
9
votes
2answers
4k views

What are the differences between matter, dark matter and antimatter?

I thought dark and anti matter were kinda the same, but after saw a video, they mention that dark matter is not antimatter but their explanation is a little fast so I got doubts. What are the ...
11
votes
7answers
1k views

Do we know the exact spot where big bang took place?

If you rewind the universe back 14,7 billion years, all matter were in one spot, and then started expanding. Do we know where this is in reference to our own solar system? And is there anything there? ...
2
votes
1answer
42 views

What does an Einstein-De Sitter universe look like?

I know an Einstein-De Sitter universe is a "flat" universe, i.e. with a K ("bendiness", sorry, don't really know what to call it in English) factor of 0, but does that entail anything as to its ...
0
votes
1answer
60 views

TIME TRAVEL-Can it be really done? [closed]

Is it posssible for us to time travel? Is light essential factor or the dark matter and dark energy?
4
votes
2answers
85 views

Conversion of matter into antimatter

Is it possible that the intense gravity of a black hole converts matter into antimatter? Does this mean that matter or energy that goes inside the black hole is converted to antimatter?
8
votes
3answers
370 views

Could there be dark matter black holes?

Could dark matter compress and form black holes? Since dark matter is even more abundant than normal matter, a dark matter black hole should not be rare...right?
3
votes
3answers
456 views

How does gravity interact with a photon?

If photon is mass-less and gravity can interact only with matter, then how does gravity alter the trajectory of light?
2
votes
1answer
89 views

If oxygen were pumped into space where would it go?

If an astronaut went into space with a sealed container of oxygen and opened it up in space and let all the oxygen go, what would happen to it? would it all just dissipate into some other particle or ...
3
votes
2answers
114 views

How much larger would a star have to be to cause thermonuclear reactions if it was made out of mostly rock like Earth, instead of gases?

I assume it would have to be considerably larger since rock isn't as flammable as gases are? But it's also more dense to begin with.. Do we know of any suns that are made like this? Is it even ...
4
votes
1answer
150 views

When the universe expands does it create new space, matter, or something else?

I am wondering what exactly is meant when it is said the universe expands. Does it simply create new space for matter to fill, does it also create new matter/dark matter to fill that space, or am I ...
2
votes
1answer
296 views

Mass distribution in the early universe

The latest big quasar find at ~12.8 bn LJ with an estimated mass of 12 bn M☉ (see e.g. http://www.newscientist.com/article/mg22530104.000-ancient-black-hole-had-an-inexplicable-growth-spurt.html) puts ...
8
votes
1answer
169 views

Can a black hole reach a limit where it can no longer attract more matter?

Can a black hole reach a limit where it can no longer attract more matter? If so, what happens with that black hole? Does the black hole die? Does the black hole decrease its size?
0
votes
1answer
171 views

Black Hole, Object or Portal? [closed]

Some say that a black hole is a rip in space-time, a portal linking two points in the universe as one. How sound is this? I've read that when a giant star collapses, what is left behind (a massive ...
9
votes
1answer
236 views

Where is all the antimatter?

The universe supposedly started off with equal parts matter and antimatter and they are said to annihilate each other. Also, nature is famous for it's balance between everything. So all we see is ...
8
votes
2answers
88 views

Neutrino interaction with dense molecular structures

Would dense molecular structures on heavier planets (crystalline or other compounds which are generally unknown to us) allow neutrinos to pass through as easily as on Earth?
10
votes
1answer
206 views

Are there any alternative explanations for the gravitational force we attribute to dark matter?

It always seemed counter-intuitive to me that we observed an measured a gravitational force and since the universe has not enough mass to account for it, the conclusion was to say there's a different ...
9
votes
1answer
88 views

How does interstellar matter density vary?

Answer to my question partially answers this one, about density of intergalactic matter and matter within galaxy: But it is mostly a hot, ionized void. How void? The density of the intergalactic ...
14
votes
1answer
209 views

Dark Matter Particle Candidates

Dark matter appears to dominate the matter component of the universe as compared to luminous, or baryonic, matter. Though it does not interact electromagnetically (it doesn't absorb, scatter, or emit ...