Recent content by SD das

Why we can't find the centre of the expanding universe?

if GR is correct about spacetime (expanding of space) then i think time travel in back (back to the past) is impossible... suppose before 2 billion years ago (from now) the total space (volume) of universe was "X" so, it's clear that the space (volume) of the present universe must be greater...

Note 3: What makes a supermassive black hole move through space? https://physics.stackexchange.com/questions/26153/what-makes-a-supermassive-black-hole-move-through-space

Note 2: Black Hole Puts Dent In Space-time...http://www.space.com/1976-black-hole-puts-dent-space-time...

Note1, Metric Expansion: https://en.wikipedia.org/wiki/Metric_expansion_of_space

Why not? ... In large scale the distance between two distant galaxies increases due to the metric expansion of space... so since a black hole is an entity in a galaxy it will move too... besides it is known that a black hole put a dent in the spacetime, a dent means, break, crush, cripple...

you say misconception but (1) what is a misconception I don't get, besides (2) are you saying spacetime is described by metric tensor but I see it is described as, "In the mathematical field of differential geometry, a metric tensor is a type of function which takes as input a pair of tangent...

I was wondering that consequence of curvature of spacetime caused by an entire galaxy! Can anyone suggest?

Einstein's general theory of relativity describes the stars distort spacetime fabric and it appears a black hole makes a hole in the spacetime fabric. It is evident that the size of a galaxy does not change due to gravity but in large scale the distance between two distant galaxies increases due...

Correct if I'm wrong. V(esc.)=(2GM/R)^1/2 that is equal to R=2GM/V^2 putting v=c,we get R=2GM/c^2 by putting the value of G,M,C we get schwarzschild radius=1.46*10^-27 m/kg

Use E=mc^2 n another relation in which uses T of this relation~ N with plank relation E=hv, v=1/T n try[emoji4][emoji4]..

Or it maybe that there is some as yet undiscovered particles that makes up of the dark matter, it may be that the dark matter is actually our misunderstanding of the laws of gravity, or or it maybe something else entirely that we haven't even thought of yet[emoji44]

What is exactly the dark matter? There are lot's of things hitting at a particle nature of dark matter I mean observation of the bullet cluster, freeze out times in the earlier universe, the third peak in the CMB power spectrum. I think there is no known consistent explanation by modified...

Today when I ask a professor about maxwell eqation He tells me " it seems that the unknowns exceed the number of equations. What are the missing ingredients? The answer is the boundary condition .With appropriate boundary conditions, zero divergence and zero curl will nail down a unique solution...

Thank u sir, for ur response..