Schneibster

The easy answer is because the uranium atoms still have the same momentum, and it is momentum that is conserved in the interaction between the probing beam and the substrate being probed. However, there is also a microscope called the "atomic force microscope" in which the atoms do not move and therefore have both the short wavelength you mention, plus no motion of a beam so not much momentum, and for some purposes these are very useful. Look up "AFM" and "atomic force microscope." I think there's a pretty good Wikipedia article on it.

The two easy answers are, 1. Because they're made from stars that were rotating and angular momentum is conserved; and 2. Because they can which seems like a smartass answer but is actually quite interesting and provocative if followed up upon.

I'm reading Sterling's Schismatirix Plus and looking at the three-volume updated John Shirley trilogy, Eclipse with some anticipation. It's time to remember the heady days of cyberpunk, when I was a godlike programmer and we were gonna run the frickin' world and duel with the rich and greedy forces of evil for control of the 'Net. I'll probably read William Gibson's Neuromancer books next.

Acme is purveyor of another wisdom: elbow grease is not a bad solvent either.

Oh you dog, I'm so jealous. My wife is ill so I am eating rather sparsely since our famous sashimi and sushi meal. (I was happy she kept it down. She's getting better. She's tough.) However, I think she will take genmai cha (green tea made with puffed rice) and steamed rice this evening, and I will probably steam a weisswurst and a tamale, and poach some of the white sticky rice we made for the sushi feast. A very cosmopolitan meal: german sausage, japanese rice, and a mexican tamale.

No. We're telling you if you get in a car right now and accelerate away from a house, you will feel acceleration forces and the house won't. swansont and Strange have both said the same thing I did, in different ways. It's all the same thing.

So, what are you eating?

The washing tablets may contain enzyme cleaners which work differently from solvents and are much less likely to damage whatever the boots are made up of, as well as more likely to work on ink than solvents.

Earth doesn't undergo unbalanced acceleration forces. Only you do.

And of course, davidivad, your perspective is confirmed by the Casimir Effect. I particularly enjoyed your imagery of the metrics fighting for equilibrium.

There's no such thing as anti-gravity. It's like anti-space. Meaningless. There is contragravity; it's theoretically possible to superimpose two gravity fields on one another such that, over some region of effect, the net gravity is zero, or opposite to the gravity of one of the fields that the user wishes to cancel. However, it takes an entire planet to hold a little teeny piece of paper down, and I can momentarily counter all the force of that entire planet on that piece of paper with a breath. Maybe one day we'll know enough about gravity to generate it using something other than planets and stars. Until we do, contragravity is a dream; but not an impossible one. So to answer your question, substituting contragravity for impossible antigravity, yes, gravity waves can produce momentary contragravity, if they are strong enough. However, the gravity waves we can see in the CMBR aren't, and unless a pair of black holes in close orbit comes flying out of nowhere and passes through our Solar System we'll never see any that are strong enough to make more than a tiny contragravity effect; so far we've never actually directly measured a gravity wave, even using miles-long laser beams and incredibly sensitive detectors (the experiment is called LIGO and is a single google away; the top hit is probably the experiment's web site). And BTW such a pair of black holes would probably irreparably damage our orbit and likely exterminate life on Earth, not to mention irradiating us with X rays. So the fact we'll never see it up close and personal is probably a Good Thing.

No. The spring will remain stretched to the same extent in both cabins. Acceleration stretches the spring, not speed.

So-called "dark energy" is a consequence of General Relativity. Just as with gravity, Cosmological Constant, aka "dark energy," is a curvature of spacetime. However, this particular curvature is not dictated by the presence of mass-energy; it is an inherent property of spacetime itself, just as the FLRW metric (Friedmann-Lemaître-Robertson-Walker, for its discoverers) is. However, because it is associated locally and not globally, as the FLRW metric is, the expansion of space increases Cosmological Constant. That is, as space expands, the total amount of Cosmological Constant in the universe increases. As Cosmological Constant increases, so does expansion; that's what Cosmological Constant governs, the acceleration of expansion. I should give Cosmological Constant its standard name, lambda, or Λ, and note that it is one of the components of ΛCDM cosmology, which is currently being referred to as "The Standard Model of Cosmology." I'm prepared to have a long discussion on the subject, but will wait to see what others have to say.

In keeping with my standard technique, I offer this answer to the thread title for your consideration: Because it's physically impossible to rotate that far in a time dimension that has a hyperbolic relation to 3-space.

Good question; as a schneibster (i.e. asker of inconvenient questions), I give you a +1. The answer is, gravity acts at the speed of light. Other cosmoses that are "nearby" (whatever that means) to us, are still so far away that their gravity cannot have reached here by now. And they're getting further; because of dark energy, if they didn't get to us by seven billion years ago, they're not ever going to, because expansion started accelerating then and that means it's too late.

That's solipsism. It's also anti-scientific. Measurement is the one and only way we have to understand the world. Other relations to the world are possible; Zen and similar disciplines teach one to see the world without measuring. And they hold some wisdom. But they do not hold knowledge of the world; only knowledge of oneself. For knowledge of the world, we have only measurement and ignoring it breeds only confusion. Then how come the muons that are going faster take longer to disintegrate? And, can you predict how much longer? Is time an illusion too, according to you? Good explanation, +1, but you skated very, very close to the edge with "time stamps." You are in territory that has led many astray, including the younger me. Remember the relativity of simultaneity. You can probably make your statement completely correct and satisfy a fussy old man like me by saying "local time stamps that are simultaneous in the observer's frame." Note on the quote system: weirdly, I quoted michel, then made an unlabeled quote of michel, then quoted Spyman-- and all three quotes now don't appear with names! So michel, the first two are for you, and Spyman, the third one for you. No doubt I'll figure all this out and get settled in soon. Edited to add: And now it works again!!! LOL. That was definitely weird.

No. I disagree with interfering with anyone that way. No one deserves to be harassed. I think you play a dangerous game. I have never used, and will never approve of, such tactics. Their primary effect is to convince the opposition that one is unreasonable, and even incapable of reason. Be the change you want to see. There are many more effective ways. I use those: contributing money to orgs that work legally and legislatively for change. Contributing time to them doing volunteering. Doing outreach. Showing up and speaking out when it's time to speak up. Taking the time to really deeply learn about the controversy so I have the facts that support my position at my fingertips. Responding with resolution to harassment. Sometimes I do something beautiful. I sent some pizzas to the Occupy protest in New York.

Let's try a one-liner: In your frame, the stick is longer or shorter. That means nothing to the stick. Now I will read your post in detail and respond where appropriate. Please be patient while I experiment with pedagogical techniques until I find the one that works for you. OK, well I contend that perspective is, in fact, not an illusion but a measurable fact. And I have evidence to support my claim: I can measure an objective change in the stick, i.e. its angular width in my frame of reference, as observed from zero/the origin. This is undeniable. At no time does the stick change, in the frame of reference of the stick. This also is undeniable. So, which is "true?" Correct answer: yes. So with Lorentz Transformed coordinates. WYSIWYG is, in fact, the truth. Remember that mesons with known lifetimes show increased lifetime when their average velocity (dangnabbit, I keep doing this. I mean speed!) is higher. This is not an illusion. It is a measurable fact. We can measure the time dilation. It's not a theory. It's a measured fact. Then remember that from the mesons' own frame, their lifetime is normal. The only possible resolution of the paradox is that the rate of time measured on remote experiments is variable, but the rate of time measured on local experiments is not. IMVVHO, this is the central fact of relativity, but I expect there are many other perspectives.

Here's a simple case that will help define where the poles/zeroes are for you, md65536: Suppose one twin goes to point A, five light years away, at 0.8c and gets there in seven and a half years by his clock. Now suppose he stays there, and the other twin comes to him. When the other twin arrives they'll be the same age again, and they'll both be fifteen years older. The fact that, simply having the first twin turn around and come back, as opposed to the scenario I have just explained, makes such a huge difference in their histories, suggests that the act of rotating makes all the difference. Einstein referred to this as "Mach's Hypothesis." Another pedagogical trick to make this clear to you is to say that, in my case, neither twin sees the entire universe rotate; however, in the original case, where the first twin returns, from the first twin's point of view the entire universe rotates 180 degrees. And this is, in fact, apparently a huge difference; look at the results.

Let's start with the basics. You can see that if you're over here, closer to where event A is going to happen, you'll see event A before event B which is over there somewhere, but if you are instead over there, by where event B is going to happen, you'll see event B first. Right? This seems extremely simple, but it is a lemma of relativity. Part of why Einstein was such a genius is because he never forgot that the simplest stuff is where it's easiest to make a big mistake you won't find out about until a lot later. Now, that means you can define one "frame of reference" where zero/the origin is over here by where A is going to happen, and another frame over there by B. And that's because the speed of light is finite. This is the simplest demonstration of the principle. You may be thinking of others, and should ask all about them to refine your understanding. That's the right thing to do on a forum like this. Yes; if you observe identical objects, moving at different speeds (note: not velocities! I mean the scalar!) relative to you, then the one with the higher speed will appear shorter along the direction of travel. There is an exact mathematical relation that describes this; it's called the "Lorentz Transform" and was discovered a hundred and fifty years ago or so. Above you expressed incredulity at this. Perhaps you will find it easier to think that a moving object appears shorter to you for the same reason a stick appears shorter when you're looking along its major axis than when you see it from the side. In one view, the stick looks like a spot; you can't see the length. In the other, it's obvious that length is its major attribute. In no case, however, does the stick change, in its own frame. In exactly the same way, the speeding stick will appear shorter, because it's rotated some of its length into time. And this appearance is no more an illusion, than the change of the angular width of the stick is an illusion when you turn it. What swansont and I are telling you is that, in fact, this is the real actual state of affairs. If the stick is flying past you at a large fraction of the speed of light, and you measure it using a super-fast theodolite (this is an automatic-tracking telescope that is used for, for example, tracking rockets in flight), you will measure it as considerably shorter than if the stick is then slowed down and brought back to you to measure at zero speed. Light is all you have to use to measure it, you see, and light's speed isn't infinite. And that's why things must be that way. To me, the most amazing thing about relativity is that once you finally "get it" you feel like Captain Obvious, Master of the Foregone Conclusion.

I think the most amazing thing about it is that after you understand what they're talking about, you can actually see it in the CMBR large scale sky maps. There's some other detail buried in those maps, too, as I recall; one big "cold spot," and another large scale asymmetry that I can't quite recall. All in all a highly satisfying scientific find. As for Linde celebrating, well he should; I hope Guth and Vilentkin had some champers too. Guth's was, after all, the original paper.

I'm not quite clear on what you're asking. Why the Libertarians... what? Later: I guess it really doesn't matter what political party it is, I'd be unhappy with anyone following scientists around and harassing them about their results. We're not just talking standard science crankery here, you know, "my great new theorie that proves teh Einsenstein is teh WR0NG" or whatnot; this is actual IRL harassment of scientists with the intent to interfere with their work. The lawsuit is not Dr. Mann being whiny. These people are actually interfering with working scientists, and not only that but on a subject that is of pretty high importance, though low urgency, to everyone. This needs to stop permanently. Bible cranks spouting baby stories about "arks" and making museums with Jesus riding tyrannosaurs and so forth is a minor irritation compared to receiving FOIA request spam.