-
Posts
54133 -
Joined
-
Last visited
-
Days Won
303
Content Type
Profiles
Forums
Events
Everything posted by swansont
-
-
It's a bias field (aka "C field") coil for an atomic fountain clock.
-
No, it wouldn't. Relative to any inertial observer, it goes as the speed of light. If one is asked the question, you can stop after "it's impossible to travel at the speed of light, see the Lorentz-Einstein formulas."
-
Why is it so warm on the moon?
swansont replied to losfomot's topic in Modern and Theoretical Physics
-
-
Your first question makes no sense to me. Your second - no. The observer in an inertial frame can always consider himself to be at rest. There is no difference, however, if you assume the object to be at rest. You get the same answer. If you don't, then you have made an error.
-
DARK IN HERE A woman takes a lover during the day while her husband is at work. Her 9 year old son comes home unexpectedly, sees them and hides in the bedroom closet to watch. The woman's husband also comes home. She puts her lover in the closet, not realizing that the little boy is in there already. The little boy says, "Dark in here." The man says, "Yes, it is." Boy - "I have a baseball." Man - "That's nice." Boy - "Want to buy it?" Man - "No, thanks." Boy - "My dad's outside." Man - "OK, how much?" Boy - "$250" In the next few weeks, it happens again that the boy and the lover are in the closet together. Boy - "Dark in here." Man - "Yes, it is." Boy - "I have a baseball glove." The lover remembering the last time, asks the boy, "How much?" Boy - "$750" Man - "Fine." A few days later, the father says to the boy, "Grab your glove, let's go outside and have a game of catch." The boy says, "I can't, I sold my baseball and my glove." The father asks, "How much did you sell them for?" Boy -"$1,000" The father says, "That's terrible to overcharge your friends like that...that is way more than those two things cost. I'm going to take you to church and make you confess." They go to the church and the father makes the little boy sit in the confession booth and he closes the door. The boy says, "Dark in here." The priest says, "Don't start that $%*& again".
-
What are higher dimensions for?
swansont replied to Phi for All's topic in Modern and Theoretical Physics
-
Speaking of coils, I wound one recently and am getting set to measure the field uniformity.
-
What I believe is that any post that long that contains no math is philosophy, not science. I believe that quoting the entire post to make a one sentence comment is a rude waste of bandwidth (not that bandwidth matters like it once did) I think that saying that we are orbiting binary stars is demonstrably wrong. Any conclusion drawn from an invalid premise is itself invalid. Not that any of that matters - tell me how you can say for sure we are moving and something else is at rest, or vice-versa. Relativity works. It makes testable predictions that have held true. It is falsifiable. "Grounded doesn't like it" is insufficient reason for me to discard it. Go show where it's actually wrong.
-
I do have a basic idea of 'jokes that will get me slapped' or 'jokes that will eliminate the chance of another date.' It's not foolproof. Women claim to like guys with a sense of humor, but they are, shall we say, 'highly nonlinear.'
-
Well, yes. But posting a joke isn't necessarily an endorsement of that point of view.
-
A fresh-faced lad on the eve of his wedding night goes to his mother with a question that had been puzzling him for most of the day "Mom" he asks "why are wedding dresses white?" The mother looks at her son and replies, "Son, the color is symbolic of the bride's purity of spirit and devotion." The son thanks his mom and goes off to double-check this with his father. "Dad why are wedding dresses white?" The father looks at his son in surprise and says, "Son, all household appliances come in white."
-
A young bloke has started work on at a large ranch, and the boss sends him up the back paddocks to do some fencing work, come evening hasn't returned. The boss gets on the CB radio to check if he's all right. "I've got a problem, Boss. I'm stuck 'ere. I hit a pig!" "Ah well, these things happen sometimes," the boss says. "Just drag the carcass off the road so nobody else hits it in the dark." "But he's not dead, boss. He's gotten tangled up on the bull bar, and I've tried to untangle him, but he's kicking and squealing, and he's real big boss. I'm afraid he's gonna hurt me!" "Never mind," says the boss. "There's a .38 under the tarp in the back. Get that out and shoot him. Then drag the carcass off the road and come on home." "Okay, boss." Another half an hour goes by, but there's still not a peep from the young fella. The boss gets back on the CB. "What's the problem, son?" "Well, I did what you said boss, but I'm still stuck." "What's up? Did you drag the pig off the road like I said?" "Yeah boss, but his motorcycle is still jammed under the truck."
-
Yes. An alpha is a He-4 nucleus. So the final product will have 14 fewer protons and 14 fewer neutrons.
-
The internet is littered with people who think that relativity is wrong. They, almost universally, don't understand relativity. Time dilation experiments have been done. And are done, on a continual basis, with GPS satellites. Relativity has been confirmed many times over again. If you want to discard it, you have to come up with something that explains all that relativity does.
-
If you solve the QM "particle in a box" for the universe (solve it for length L and then let L get very big) you get an answer that looks like (n +1/2)hbar*w for each of the infinite number of modes. n is the occupation number, or number of photons in that mode, and w is the frequency. That means that even if there are no photons, there is an energy of hbar*w/2, and since there are an infinite number of terms, that sum is infinite. Physicists have long recognized that this infinity is meaningless and that the relevant energy quantity is the difference between two states. The perpetual motion proponents want to tap into that infinity, but it's not real. The force between parallel conducting plates is the Casimir force. When you solve the same equations for the plates, there aren't as many states - because of the boundary conditions, you can't have any modes with a half-wavelength longer than the separation of the plates. Those modes are absent, and the difference between the inside and outside energy exerts a force. (there are also interesting effects of suppression or enhancement of atomic de-excitation. You can keep an atom from decaying to the ground state in a properly prepared system, or you can make it decay faster than the free space equivalent) The problem is that though the force is real and does work, it requires work to assemble the system. It's not a perpetual motion source.
-
Any site that is trying to hype perpetual motion is probably not the best source of info on ZPE.
-
Note that magnetic forces do no work. You can't extract any energy from them directly. Good drawing or no, it won't work. Mother nature is a bit of a hard case when it comes to trying to violate the first and/or second laws of thermodynamics.