markovchain
  • Member for 8 years, 10 months
  • Last seen more than 1 year ago
5 answers
votes
3k views
Does the amount of gravitational potential energy in the universe increase as it expands?
Accepted answer
8 votes

That's actually a tricky question. The short answer to the title question is yes, it does. But the answer to the follow up question about conservation is, it is still conserved. In a much simpler ...

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15 answers
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100k views
I don't understand what we really mean by voltage drop
5 votes

I'm not a physicist, rather a simple engineering student, and I believe your confusion has confused me, too. That's great, because it made me look for the answers myself. This is just my personal ...

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2 answers
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2k views
Why do we need a Theory-Of-Everything (TOE)?
4 votes

The correct answer is probably a subjective one, but if by "need" you mean a basic necessity, something without which we cannot survive without -- then no, we don't need a TOE. If humans never evolved,...

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4 answers
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4k views
Since there are gravitational lenses, are there gravitational mirrors?
4 votes

Gravitational mirrors are possible, but it would be a very unstable mirror. Nonetheless, they are possible. Just before the event horizon of a black hole, there exists a place called a photon sphere. ...

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4 answers
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236 views
Constructing an orbital trajectory that quickly returns to its origin
Accepted answer
3 votes

All the following is simply a simple application of math. If I'm wrong anywhere (and I'm bound to be), please feel free to point it out to me or just edit the post, if you like. The largest planetoid ...

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3 answers
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2k views
Couldn't we measure electrons with good enough technology?
1 votes

That effect you're referring to is the observer effect, wherein the act of observing something changes the thing we observe (and when used on people, interestingly, it's called the Hawthorne Effect -- ...

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2 answers
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4k views
Does mass as a measure of inertia have a meaning in zero gravity?
0 votes

Yes, mass has meaning in zero gravity You are confusing mass with weight. Mass is the "amount of stuff" that is constant in whatever gravitational field the object is in -- even in 0g. Picture this: ...

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1 answers
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194 views
Understanding that nothing can go beyond the speed of light
0 votes

You're imagining light as a solid, rigid body that can instantly get from point to point. You're still thinking in terms of small distances. In fact, what will happen is that when you move the laser, ...

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