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About J.C.MacSwell

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  1. Rotation and gravitational potential in relativity.

    The gravitational potential will increase due to the spin, as will the rest mass of the ball/system. The rest mass and relativistic mass will increase due to the sum of the increased relativistic masses of it's parts. In it's rest frame the rest mass and relativistic mass is the same thing though.
  2. Yeah. Go Physics! An early sting or bite should surely keep them from too much focus on Biology...
  3. Ultra violet catastrophe and Plank's theory

    Thanks. Is this true just classically, or true in any idealized case? (I pictured the last quantum step getting to the goal line)
  4. Ultra violet catastrophe and Plank's theory

    Why not? In this hypothetical scenario empty space would effectively be at a temperature of 0 K. Your blackbody would tend to that.and have no reason to radiate further as it reached it. The reason you can't get anything to 0 K is that there is no 0 K space around to be utilized to allow it...your hypothetical does not exist.
  5. 'speciation reversal'

    Not an expert on evolution or even a biologist but I think I have assumed this (speciation reversal as a potential and likely process) as obvious once I realized that the definition of species is less rigid than I was originally taught back in grade school. I guess the devil is in the details.
  6. Water has calories

    Yeah. I think it stands as part of the equation, but there are a lot of interdependencies involved. Best to jog a couple miles before relieving the kidneys...just to get that core temperature up!
  7. Water has calories

    A food calorie is actually a kilocalorie of energy. Otherwise I would simply have a nice cold beer and lose weight. (after it goes through my system) So a litre of water at 38 C would net me 1 food calorie equivalent (1 degree above my body temperature) A litre of water at 0 C would save me 37 calories worth of dieting But it has no actual food calories as mentioned above.
  8. Energy, Cost and Subsidy in Power Production

    So...is taking oil out of the ground without paying the current and future damages it causes effectively, if not literally, a subsidy?
  9. Removal of the down-vote, yes or no?

    What if we could still negative a post, but it would not count against the poster unless they are currently positive? That way for new posters you can attack the post, but not the poster. It would give them some level of amnesty. They would still be subject to following the rules, subject to suspensions etc, which I think is generally pretty fairly regulated, but a little more forgiven otherwise.
  10. Removal of the down-vote, yes or no?

    Over time it might. Let's say a new member who wants to learn has -10 the first month, but after 6 months is a -15. They have actually improved but the reputation system says otherwise. If you want them to care about rep they would be better off opening a new account. If I see a good question but know the science is incorrect I never down vote it but some do, especially if the poster has asked a similar question before. I tend to not want to up vote it if the science is incorrect. If someone is poor mannered they are more likely to get away with it if their science is correct, so a double standard with regard to that seems to be in place. So yes, ideally they gain it back over time, but I really don't think it happens readily for those just learning. So they can carry negative rep for some time.
  11. Removal of the down-vote, yes or no?

    I had made a suggestion a while back but IIRC it wasn't feasible because of a software change requirement or something. Basically it would add points over time to anyone with negative rep, since it seemed new members would tend to get it and not have time to adjust, understand the rules (such as speculating in good faith but in the wrong forum type of thing) They could be potentially solid members but would carry that negative rep for some time. Maybe if a mod would simply clear it after 30 days they could have a fresh start. It is after all a system where we want members to actually care about to some degree about their score, especially if negative and it is much easier to get negative (just start insulting) than positive (well thought out or helpful) rep.
  12. Rotation - is it absolute?

    Agree essentially but still perhaps not absolutely. We do not know what is beyond our fixed stars (observable universe), so cannot say definitively that it is not rotating wrt something greater or other, if given that inertial frames can be produced that rotate wrt it as the Wiki article suggests. This was what I meant when I posted previously:
  13. Rotation - is it absolute?

    I would certainly agree with that part. Did not know there was an absolute reference frame in GR. Do you have a link for this?
  14. Rotation - is it absolute?

    In there simplest and most straight forward form? Because it is not an inertial frame.
  15. Rotation - is it absolute?

    One where Newtonian physics, to a close approximation, does not apply. If you mean more precisely than that, LOL, I would not! You mentioned this earlier, can you elaborate on the point you are trying to make and how it relates to absolute rotation?