Recent content by GW150914

Let's take a Schwarzschild black hole as an example. For a Schwarzschild black hole, we have $${\rm d}s^2=-\left(1-\frac{2GM}{r}\right){\rm d}t^2+\left(1-\frac{2GM}{r}\right)^{-1}{\rm d}r^2+r^2{\rm d}\theta^2+r^2{\rm sin}^2\theta{\rm d}\varphi^2$$So the metric tensor ##g_{\mu\nu}## has only...

Here's a link to Wikipedia on this solution: https://en.wikipedia.org/wiki/Misner_space And here's the pdf file for the paper listed on bottom of the Wikipedia page: http://iopscience.iop.org.sci-hub.cc/article/10.1088/1475-7516/2004/08/004/pdf

According to the Bekenstein–Hawking formula in black hole thermodynamics, $$S=\frac{kAc^3}{4G\hbar}$$ Consider a Schwarzschild black hole, we know that $$r_{\rm g}=\frac{2GM}{c^2},\ A=4\pi r_{\rm g}^2$$ Therefore, we can get $$M^2=\frac{\hbar c^3}{4\pi k_{\rm B} G}S$$ From thermodynamics, we...

What would the world be like if the speed of light is infinity and the Planck constant is zero (therefore the world is totally Newtonian)?

What does "PITAs" mean?

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Thanks dude but Admin Greg Bernhardt has already helped me changed my birthday lol Thanks you all for helping me!

Thanks, I'll just wait till he comes back lol it's not really a big deal

What is strange, however, is that in Star Trek Voyager, there're some episodes in which Captain Janeway mentioned anti-gravity thrusters, especially when Voyager was trying to land on a planet's surface. Besides, a few modification on inertial damper can create a nice anti-gravity drive, and...

Almost a month. I asked him on June 19th.

I want to modify my birthday but the guy (Greg Bernhardt) who sent me a welcome mail haven't answered my request yet.

We all know that starships in Star Trek have artificial gravity. They also have inertial damper. Therefore, we can conclude that they have the ability to counteract gravity. However, as those technical manuals of Star Trek tell us, starships are using impulse drives for slower-than-light...

Amazing news, thanks for sharing it!

Well you guys have made perfect sense, so perhaps I have to get use to python...

Mathematica is fully functional for daily astronomy data analyzing works, and it is much more convenient than python, so why can't them use Mathematica instead of python? It's like when you have warp drive you still travel through space using chemically powered traditional rockets, which is...