Schneibster

No, I didn't say describe it, I said define it. Have you ever used an oscilloscope? Do you know what the "trigger" control does? And do you understand that by manipulating the sweep speed, you are defining the oscilloscope's frequency, and comparing the signal's phase with it, using the trigger to control the relative phase? Now, that oscilloscope (and I have two in my garage, one in need of calibration) is calibrated so that those sweep speeds are extremely precise; this allows extremely precise measurement of frequencies and time intervals, which is one of the main functions of an oscilloscope. In addition it is calibrated so that its voltage scale is also extremely precise. These are adjusted by a professional calibration service, that maintains the special batteries that are certified to provide exact voltages, and the special oscillators that are certified to provide exact frequencies, so that I don't have to have such incredibly expensive and touchy devices. So "phase" is defined in terms of an exact time reference, compared to a reference frequency: the oscilloscope. There is no absolute phase. Phase is always a comparison between two signals: a reference and a datum. The oscilloscope provides the reference with its sweep speed, triggering adjustment, and variable holdoff reference. And even then the variable holdoff is used by defining the beginning and ending measurements. "0" is basically meaningless, though they put it close enough that you're guaranteed to be able to measure a full screen width. It can't be kept that tight; you have to measure it relative to itself every time, two numbers not one. You know the little knob that looks like a safe combination dial? That's the variable holdoff; the one you use to get four digits out of the 'scope when you're measuring. Against the reference. Cute math. Now let's talk about reality. Never argue with a sound engineer about sound. And never argue about waves with an EE.

Define phase.

Phase is a meaningless word unless two waves are compared. Never argue with a sound engineer about sound.

How about the giant fungus under (IIRC) Minnesota? Later: did a little research, the one in the Northern Midwest has been eclipsed by one in Oregon: http://en.wikipedia.org/wiki/Largest_organisms#Fungi 2400 years old. Hmmm. Aren't bristlecone pines older than that?

In fact this is incorrect. If you reverse the phase of one speaker of a stereo pair using a stereo source program, you will be able to hear the difference. Furthermore, you can also hear the difference if you use headphones, in reversing left and right, or reversing the phase of either one alone. This is standard audio engineering. I can present links to a couple good books on it, but personally I learned it by experimentation in the real world. You can avoid this by reversing the phases of both speakers simultaneously. All of this also applies to 5.1 and 7.1 systems. In fact, phase is even more important with such complex setups.

I know a man who thinks womens' college basketball is the ultimate distillation of the game. I'm not sure I disagree; I have rooted for the Stanford women numerous times. They nearly went to the Big Dance this year and they are perennially close. I spent a night on vacation once upon a time, with the Schneibsteress who is an inveterate sports fan, in the hotel room watching the Stanford game, Elite Eight or Final Four, I don't recall which, because they closed down the bar and turned off the TV before it was over. Furthermore, Naismith originally developed it for college. It's respectful of the game. And I cheered myself hoarse for Brandy Chastain. And I think she should be able to take off her jersey if she wants. Girls with big knockers walk around in bikinis all the time. Pretty outrageous bikinis, on occasion, too. She was just being elated, and what she did justifies that. I would never criticize. I might get a bit sarcastic about it if she took off all her clothes. Just her sports jersey? Get over it. Good for her.

Yes, so I guessed. Good thing. Glad it worked out the way you wanted.

Enthalpy you're being a one-trick pony: no nukes. This despite the fact you don't seem to actually understand how they work (you claimed the TWR wouldn't work based on the opinion of a single nuclear engineer who has a financial stake in it not working, for example). Do you believe you can stop the Chinese and Indians from building power plants? (BTW I should note than when I say, "Indians," I always mean people from India, never First Americans.) If not, then why are you insisting they build out coal-fired ones instead of nuclear? Do you not "believe in" global warming?

It was in independent testing by two different firms. Whether it's still true in the last couple years I don't know; I bought a five year multi-system license and have never looked back. Got a pretty good price break from their standard thirty simoleons too. I have never had anything to complain about that turned out to be them. The one time they made a false positive on my system the next update (two days later) fixed it. That alone blows Kaspersky, Norton, and McAffee out of the water; their customer support all sucks. Maybe you're OK with waiting six months for your vendor to fix a false positive; I'm not. That's simple laziness and disrespect for customers. Eset is fast and it doesn't miss anything I've ever found. I went to the testing firms to decide what antivirus to buy, not to the antivirus vendors to check their claims. I do not work for Eset or hold stock or know anyone who works there. Please don't make veiled accusations without evidence. It's impolite. Not to mention, are you arguing about firewalls or antivirus? You seem confused.

No.

Yes. This is how cosmologists say how long it's likely to be until the universe undergoes the Big Rip. Remember though that the fact that we no longer feel its gravity doesn't mean the rest of the universe doesn't. In fact, somewhat more than a third of the visible universe still does; it hasn't disappeared over their horizon.

Be very, very careful saying the ear is not sensitive to phase, studiot. In fact, the ear is very sensitive to phase and uses it to provide direction information. That's the reason for all the intricate whorls and ridges in your external ear. Furthermore, the cochlea has muscles that allow it to filter phases, and to filter frequencies. It is this that allows you to hear a voice even over background noise. As far as the original OP, I agree with the majority of posters that this is destructive interference caused by the shape of the bell/chalice and present at certain spatial nodes and absent at others. I have experienced numerous similar effects while playing music, engineering musical recordings, arranging studios and live performance stage setups, and watching my home theater.

It is necessary to develop new intuitions, and the knowledge of when to use them. The real world is considerably different than what we think we see. Newton realized that in the seventeenth century.

Energy can be light which has no mass (though it has momentum). It can also be the twisting or stretching of a rubber band (which are in different parts of the stress-energy tensor). When the universe was first formed as we see it now, after the vacuum fluctuation and inflation, when the inflaton dumped its energy into the newly created universe and the Big Bang happened everywhere, there were all kinds of particles, but they were all in equilibrium. With such a high energy density, each particle lasted only a fraction of a nanosecond before it met an antiparticle and annihilated back into energy. But as the universe cooled, the particles started to last longer, and some of them were matter fermion particles like quarks or leptons, not energy boson particles like photons, colored gluons, or W and Z particles. Eventually the quarks mostly decayed into up and down quarks, and the leptons (except neutrinos) decayed into electrons. Why the up and down quarks were favored over antiups and antidowns is, as swansont intimates, still a matter of controversy among physicists. But that's what happened, beyond a shadow of doubt; everyone agrees on that, because it's what we've measured. Once it had then all the newly formed nucleons (neutrons and protons, respectively two downs and an up and two ups and a down) associated with electrons and became atoms. Then, because the pressure and density and temperature were still so high, about 1/4 of the hydrogen fused into helium (and incidentally also into a very small percentage of lithium, which is important because it indicates the exact conditions under which this all happened, as does the exact percentage of helium created). The rest of the elements have been cooked up in the cores of stars, then spread across the universe by supernovae and by the enormous plumes of superheated gas that we have been recently observing connecting the galaxies, and galaxy clusters, and surrounding the superclusters of galaxies, that make up our universe. I think this is a Pretty Good answer to your question, "where did matter come from."

Just to complete the picture, the flies are circling a piece of neutron star that takes up only a tiny space compared to the rest of the atom; if the electrons are flies in church the neutron star is the size of your fist. And that fist is where all of the mass of the atom is.

Snicker @ IANAM

Cheap paint thinner contains more fractions than proprietary ones, I would bet. I'd've suggested acetone but I was pretty sure if they were miniature real wellies made with rubber it would melt them.

Actually changes in the climate will wreck the US breadbasket in the Midwest. It wouldn't be a problem to move to Canada except the dirt has all been scraped down to bare rock by the glaciers and pushed south. That's why there's lots of dirt in the Midwest. Oops. So all of the US population in the Midwest will be unable to grow food any more. Meanwhile, the sea level will be rising and the storms will be getting bigger and bigger on both coasts of the US. New York is history. So's most of the LA basin and a lot of Seattle. The California Central Valley will become a sea. Florida will be a series of undersea mountains, as will most of Texas and all of low-lying Louisiana. And that's just in the US. Meanwhile a quarter billion people in Bangladesh will die. Meanwhile all the Pacific islands will be inundated, except the mountain peaks like Mauna Kea. Meanwhile half a billion people will die in China and India. Meanwhile most of Pakistan's Punjab (one of the richest agricultural regions in the world) will be underwater. I project excess deaths of 3 billion or more by 2100.

Unfortunately my research indicates that you are presenting the narrow viewpoint of one nuclear engineer, Kirk Sorenson. The community does not agree. Also, Sorenson's firm is in direct competition with TerraPower, which unfortunately makes him a biased source with a financial interest in the outcome of the argument. (For observers: TerraPower is the company Enthalpy is complaining about getting money from Bill Gates.) Furthermore you have not addressed the consumption of existing nuclear waste, which can be accomplished with no other type of reactor at all. Do you prefer keeping it in a mountain near your town, or in the pools next to the reactors where it can participate in the next nuclear accident like it did at Fukushima? There are already thousands of tons of it. What's your solution? On edit: What's the matter with using 235U to start the reaction?

I was right. You are confusing the Dirac Lagrangian with the Dirac field.

IIRC it's about 20kt/gram of annihilated matter (so a half gram of antimatter would annihilate a half gram of matter, for a total of 1g annihilated). I don't remember the figure in joules but there are numerous conversion calculators on line. It's on the close order of 10 or 20 tJ. It's about 90 tJ. Did you mean "joules" instead of "grams" above? Later: No, you can't possibly. The correct value for the energy of a gram of matter is 89,875,543,056,250 joules or 21.480770329 kilotons. That's about 90 trillion joules, or 21 kilotons in nuclear explosive terms.

You can lead a cat to food but you can't make him eat. That's a shame. Unfortunately the only alternative is to label them all psychotics suffering from delusions. That is in fact the case, but you won't get far telling her so.