Reputation
180,778
Next tag badge:
99/100 score
33/20 answers
Badges
27 307 504
Newest
 Nice Answer
Impact
~5.8m people reached

Apr
26
comment An explanation of Hawking Radiation
@ArnoldNeumaier: I didn't think Veltman discussed Hawking radiation in that book. I have the book somewhere so I can check, but I'm fairly sure it doesn't mention Hawking radiation.
Apr
26
comment The mass-energy equivalence is a principle which can not be derived from anything?
Hi Sophomore_Jinx. Your question seems an obvious duplicate to me. If you'd like to edit your question to explain what you want to know that isn't covered by the previous question I will withdraw my close vote.
Apr
26
comment How do you state the quantized radial acceleration of an orbiting electron?
Electrons don't orbit the nucleus. I assume you're referring to the Bohr model, but this is a classical model and does not provide an even remotely realistic description of the electrons in an atom. There is no radial acceleration so there is nothing to quantise.
Apr
26
comment Does the constancy of the speed of light in vacuum hold for any observer in GR as well?
I don't want to vote to close because that will close the question immediately. However I think the combination of the two questions I've linked above is a duplicate of this question. A search of this site will find many related questions.
Apr
26
comment Does the constancy of the speed of light in vacuum hold for any observer in GR as well?
Also a possible duplicate: Does the speed of light vary in noninertial frames?
Apr
26
comment Does the constancy of the speed of light in vacuum hold for any observer in GR as well?
Possible duplicate of: Speed of light in a gravitational field?
Apr
26
comment Did the Big Bang happen at a point?
Hi Avinash, are you talking about an embedding of the 3+1D universe in a 4+1D spacetime?
Apr
26
comment non constant acceleration problem
@MurrayMackenzie: yes, divide the period by four to get the time from releasing the string to the arrow leaving the bow.
Apr
25
comment Why would a black hole evaporate?
Hi Jiminion. See the two questions I've linked. Evaporation isn't due to one particle being a particle and the other being an antiparticle. It's due to one particle having a negative energy and the other having a positive energy. So your question is based on a misunderstanding of the physics involved. However I sympathise because the popular science explanation of evaporation gives entirely the wrong impression of the process.
Apr
25
comment Why would a black hole evaporate?
See also: Why doesn't Hawking radiation cancel itself out?
Apr
25
comment Why would a black hole evaporate?
Possible duplicate of: Black holes and positive/negative-energy particles
Apr
25
comment Quantum mechanics - “God does not play dice” - does he? Or might he not?
See also Is the uncertainty principle a property of elementary particles or a result of our measurement tools?.
Apr
25
comment Mechanical properties crown cap
@lucas: this is a crown cork
Apr
25
comment Mechanical properties crown cap
Hi and welcome to the Physics SE. I'm afraid this is an engineering question and out of place here. You could try asking on the Engineering Stack Exchange.
Apr
25
comment When only part of the surface an object is in contact with has friction, what is the normal force I should use?
Hi and welcome to the Physics SE! Please note that this is not a homework help site. Please see this Meta post on asking homework questions and this Meta post for "check my work" problems.
Apr
25
comment Why is 1 kg of cotton heavier than 1 kg of stone?
Possible duplicate of Is a block of cotton heavier than a block of iron?
Apr
25
comment Energy efficiency in modern houses
I'm not sure this is really a question about physics. Have a Google for heat pump and you should find useful info.
Apr
25
comment projectile motion under the influence of gravity
Hi and welcome to the Physics SE! Please note that this is not a homework help site. Please see this Meta post on asking homework questions and this Meta post for "check my work" problems.
Apr
25
comment Approximating the pressure drop for a centrifugal fan/blower
I suspect you might be better off asking this on the Engineering Stack Exchange. Although this is a perfectly good question, it's a bit applied for us.
Apr
25
comment How can Big Bang happen without time?
Was the video referring to the ekpyrotic theory i.e. that the Big Bang was the collision between two branes?