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He didn't prove anything. He couldn't do undergrad physics right.

Physicsforum explained it well at http://www.physicsforums.com/showthread.php?t=274996

The kinetic energy of the net movement of earth and of the atmosphere (in the centre of mass frame) is thermodynamically available and (neglecting friction and relativity) can accerate a sufficiently light mass arbitrarilly fast. Thus, DDWFTTW is obviously not physically impossible (and numerous conceptually-trivial schemes have been suggested).

It is empirically known that yachts or sailing boats can continuously travel diagonally with (as well as against) the wind at speeds (such that even the component of their velocity in the direction of the wind is) significantly faster than the wind.
        In the boat's frame of reference (assuming steady nonaccelerating state, inviscid flow, etc) the sail can be oriented such that any (sufficiently) diagonal headwind (or tailwind) is redirected more into the sternward direction (with the same speed, by conservation of energy), such that the reaction force on the boat (while mostly perpendicular to the keel) has a positive component in the direction of the bow; (neglecting friction) a sailboat can accelerate forward as long as the wind relative to the boat is not arriving directly from the front.
        In the water's frame of reference (assuming the boat is already moving forward) this redirected breeze is always slower than the incoming wind (draw the trig'), losing energy and momentum to the boat (later frictioned to the water), independent of how fast this lets the boat accelerate compared to the windspeed. (Learn More)

The simple idea behind the fan and wheeled trolly contraption is that the belt (which couples their respective axels) performs exactly the role of the sailboat's keel (imagine sailing on a ringworld).
        The belt/gear ratio constrains the propellor-tip to move through space on a fixed helical trajectory of constant diagonalness (the ratio of forward to transverse motion, or pitch to circumference), ensuring that (as long as the atmosphere is moving forward relative to the ground) the propellor tips are never moving directly into the wind and thus (identifying the propellor blade with a yacht's sail) a forward thrust component can be obtained regardless of whether the velocity of the cart itself is less, equal or more than the wind velocity.
        The limiting factors are the aforementioned ratio, the fixed-angle pitch of the propellor-tip's blade-sail, the windspeed (relative to the ground), drag and friction. For any constant windspeed, the ratio and the propellor sail-pitch together determine a maximum cart velocity (downwind relative to the ground) at which forward thrust can be produced (this can be larger than the wind velocity but not infinite) but it is a tradeoff because the ratio simultaneously increases drag, and (with the ratio also fixed) tuning the propellor sail-pitch for higher cart-velocity decreases its efficiency at lower cart velocities.

The 4th comment here is interesting :
http://www.physicsforums.com/archive/index.php/t-42053.html

Here is some information about the body consumption (in kcal) for many activities :
Sleeping 70
Lying quietly 80
Sitting 100
Standing at ease 110
Conversation 110
Strolling 140
Driving a car 140
Playing violin or piano 140
Hiking, 4 mph 350 407
Swimming 500 582
Long-distance running 900
Sprinting 1400

So if we say piano requires the same amount of energy as coding (I would say it requires less mental effort as people develop automatisms at it) it is 40% more consuming that being a couch potato sitting in front of a TV, but still a far cry from running or even hiking. Similar however to walking quietly, which is what my doctor recommends me to do as a minimal exercise to not get unhealthily fat.

Be careful sizing a backup generator when a large part of its load will be switching supplies and UPSes. UPSes in particular have _very_ strange load waveforms due to the rectifiers that are used in the charging circuit. The harmonics passed back on the line can cause the generator to 'seek' trying to lock in to 50/60 Hz, which can cause significant damage.

A permanent magnet generator can help, but they're a little more expensive.

http://ecmweb.com/news/electric_ensuring_generator_ups/

http://www.physicsforums.com/archive/index.php/t-186969.html

That being said, his bit about loans is only a half measure, if he was really serious he'd rescind Carter's dumbass executive order and get us down the path of recycling to deal with the "nuclear waste" issue.

Minor correction, President Reagan lifted the ban in 1981.

Apparently the ban is part of the Nuclear Non-Proliferation Act, so it couldn't have been overturned by an executive order. There's a very interesting discussion of it here. According to this article from 2008, there is still a ban in place.

I don't know why they didn't label the arrow keys on the 50G. I went through college on a 48SX, so I knew about some of the arrow key functionality, but I think only veterans of the 48 know such things. Likewise they failed to ship a full manual with the thing - I didn't even know until a couple years ago that there existed an advanced user guide on the 50G (normal guide, advanced guide - also CAS documentation). There is a ridiculous amount of hidden capability in the 50G, but they don't ship manuals for it, so nobody knows about it. And for anyone who has the 50G dropping keys on them, set the KEYTIME, another great documentation failure by HP.

As far as the swap, I'm not certain if what you call true x-y swap exists on the 50G, but if it does exist in the catalog you can probably map a soft or hard key to it. I would have to check the manual on how to do that, but I have done it before. I had to map a soft key to get back the '->Q' function that was a hard key on my 48SX (left-shift EVAL - converts a fractional number to a ratio of two integers, ex. .9225 ->Q gives 369/400).

Sigh: http://www.physicsforums.com/showthread.php?t=118133

In addition, the NATO round was designed off of the .223. It's like saying that Ubuntu isn't Debian because some of the packages won't work in it. .223 is a whole lot faster to write out and that's how it was originally designed.

http://en.wikipedia.org/wiki/.223_Remington
http://en.wikipedia.org/wiki/5.56x45mm_NATO

With the U.S. military adoption of the ArmaLite AR-15 as the M16 rifle in 1963, the .223 Remington was standardized as the 5.56x45mm. However, the .223 Remington was not introduced as a commercial sporting cartridge until 1964.

Or for the Car Analogy. It's like arguing that the Hummer H1 isn't the same as the Humvee. Even though they were designed and built by the exact same company. I'm sure a few parts aren't interchangeable, but for the most part they're the same damn vehicle.

Two points.

1) That paper is nearly a year old so the logic that "Now finally counter arguments can be heard" seems a bit specious.

2) That paper is a complete crock of unrefereed shit. I read 92-94 which are the conclusions and was so confused I went and read the earlier portions. There are numerous fallacies in their assumptions and they get some pretty fundamental thermo issues flat wrong.

      If you'd like to read physicists (not climatologist) opinion of the paper go here:
http://www.physicsforums.com/archive/index.php/t-300667.html

I think it is an alternative to string theory.

From http://www.physicsforums.com/showthread.php?t=313565 :

Compared to string theory - much simpler and works in 3+1 dimensions
Compared to LQG - the classical limit is not a problem

What does "that's simply because the electrons follow wave trajectories" mean?

Well, in classical motion, trajectories are straight lines. Add in gravity, and the lines become curves. At the quantum level, though, that doesn't apply (or rather, isn't dominant), but neither does the notion that particles *become* waves. Instead, they follow wave trajectories, rather than straight lines. Check out this article in arXiv: Understanding Bohmian mechanics: A dialogue, good for newcomers asking these sorts of questions. This site has some good illustrations of the trajectories, which were copied from an illustration on the site I first linked you to. Here's a paper from Physics Letters A will a better illustration of the trajectories (page 209).

That's precisely what "collapsing the wave function" means mathematically. We don't have a handle on what it means physically.

That arXiv article covers exactly that. Check it out.

I cannot speak to the polarizing label experiments. I'd be interested in Prof. Norsen's take on it. I'll send him a question and see if he answers. He's been quick with responses before, so I'm hopeful.

Does anyone have any more details on this Gravitational Effect?

> I have no idea what this is called but I am sure
> someone who is more gifted in physics can explain better.

Well the poster just above your post explained it quite well, I also found this link which tends to confirm the other poster explanation ;-)

http://www.physicsforums.com/showthread.php?t=289183

Basically, tidal forces leading to a lock-step. The periods would not have to be the same in the beginning.

I hope that you will forgive me, but I haven't had time to try your marble experience, thanks anyway ;-)

Cheers ;-)

Want to hijack this trollfest and see if I can get some useful information - the thing city bikes REALLY need is regenerative breaking - compared to cars, bikes suck at acceleration, and trying to conserve precious momentum makes breaking traffic laws way too tempting - some regenerative breaking would solve both problems and more.

http://www.halfbakery.com/idea/Regenerative_20Brake_20Bike here are some http://www.physicsforums.com/archive/index.php/t-206514.htmllinks but it seems while everyone agrees 'it's tricky but can be done' no one has actually done it.

Not sure why that is, any additional info/ideas would be welcome. I think it would really transform the urban environment if it could be worked out. And I have fantasies of keeping peddling at stoplights then shooting off @ proper street speeds.

Read Morbius's replies. No need for me to re-invent the wheel on the nuclear argument. But... pretty much... you're wrong about limited supplies, risk and cost. Don't drink the anti-nuke-aide.

http://www.physicsforums.com/showthread.php?t=156759

I agree that windmills wouldn't be a likely terrorist target.

Aluminum wiring is a FIRE hazard and was BANNED in all new
houses in the US due to it.

You might be able to get away with it outdoors, but it is
most likely a bad idea based on the indoor results.

http://www.physicsforums.com/showpost.php?s=7d306106c574b8acd101e052ab90be42&p=615606&postcount=6

http://books.google.com/books?id=2edigWaeGPUC&pg=PA175&lpg=PA175&dq=aluminum+wiring+ban&source=web&ots=l0eE26iMkt&sig=rVIgBVl0gXGlJicEHA_qW8s4zY0&hl=en&sa=X&oi=book_result&resnum=4&ct=result

Alot of areas you cannot even get insurance for the building
with aluminum wiring in it.

http://en.wikipedia.org/wiki/Aluminum_wiring#Hazard_insurance

Swiped from here
http://www.physicsforums.com/showpost.php?p=1002158&postcount=28

In classical black hole theory, the rate of interaction (and therefore accretion) would increase quadratically as the mass increased; that is, until it became Eddington limited. A black hole can't accrete too quickly or else the radiation pressure will blow away the surrounding matter. This results in a mass accretion rate that goes linearly with mass, leading to exponential growth of the black hole. The e-folding time for this accretion should be of order tens of millions of years. To accrete the earth, the black hole needs to undergo about 115 e-foldings -- that'll take several billion years

Basically we need another Manhattan project, but where does the motivation come from? We are not in World War II in search of the ultimate weapon, and IMO we are not yet close to a tipping point regarding global warming to make the project palatable to the public (however mistaken and short-sighted that may be).

According to http://www.physicsforums.com/showthread.php?t=245508 the Manhattan project cost $1 billion in 1945, something like $20 billion today. I also recall that the Hoover dam diverted a huge portion of its energy to the project.

So it may be some time before fusion gets the attention it needs. Until then, geothermal, wind and solar seem like relatively easier ways, both politically and scientifically, to address our energy needs.

(*) I know that's bollocks..

http://www.physicsforums.com/showthread.php?p=1759493
http://www.philforhumanity.com/Terraforming_Mars.html
http://en.wikipedia.org/wiki/Terraforming_of_Mars

The problem right now is not the temperature or the sun, we have some forms of life that could handle Mars right now, as far as I know (Asparagus, for example, as well as plenty of microbes). The problem is the plant just isn't heavy enough to keep gas close to it.

The BH is mostly radiating photons, not much massed particles. Photons are created from the vacuum around the BH horizon, and in pairs. As you know antiphotons are the same as photons, it doesn't matter which falls in the BH.

You can fall a lengthy discussion of this here for instance. (I don't generally advocate physicsforum unless you want to waste a lot of time in the details of specifics bits of physics endlessly debated).

However, this may answer your question regarding particle-antiparticle. It is much harder and much more unlikely to produce particles other than photons (photons can be produced of any energy. Particles require very precise energies to be created). BH may also produce other form of energy such as neutrinos/antineutrinos but those are massed and still much more unlikely than photon pairs.

Most importantly, the Hawkings radiation (HR) is just an explanation mechanism for the fact that BH have mass and temperature. If a BH has a temperature then it must radiate by very basic thermodynamics. HR just provides a plausible mechanism for the radiation.

If a massed particle-antiparticle pair is produced near a BH, either can fall in, not just the antiparticle if the BH is made of matter, or the other way around. As stated earlier this event is unlikely, even nigh on impossible near large BH, which polarise the vacuum very little near the horizon.

Conversely, a very tiny BH should be able to polarize the vacuum enough to produce any particle. This is right before the moment it explodes though, in a display you don't want to be near :-)

The universe likely has neutral charge. Also see a more detailed discussion on the subject.

If your argument is that mutation can't make a large jump - well, welcome to reality. Mutation makes small changes, natural selection picks among them, and over time this build up to large differences.

If your argument is that minor differences can't sum up to an "innovative" difference, e.g. eye evolution from a light sensitive patch, has been shown in rapidly in simulation using minor differences from generation to generation (.1% differences).

If your argument is that such differences would not show up in the real world, then our experience with single strand (genetically identical) mice might of interest - after 3 generations, there's measurable, inheritable size differences, which by definition is a form of mutation (even though I've not seen the direct genes for this being mapped).

For direct gene mapping, there is the repeated longitude (20,000 generation) evolution of cold-resistant e.coli, with subsequent genome sequencing and difference analysis.

These are just a few examples off the top of my head. I don't know what kind of evidence in particular you'd like, because I don't know what you know and don't know. Feel free to ask more questions, and I'll try to find time for an answer. (And sorry for the lack of references for most of this - I've got limited time.)

Eivind.

ok, I am ripping most of the info from here: http://www.physicsforums.com/showthread.php?t=122375&page=6

        "If they were able to make a small blackhole, and it got "loose" and fell to the center of the Earth, the pressures at the Earths core would force material into it so fast that even a very small one would gobble us up very fast. I am not sure what the exact pressure is at the Earths core but it could force material through even a very small "hole" very quickly. I do agree that once it gobbled up the Earth, it would just continue to orbit the Sun, and the Moon would still orbit the blackhole as if it were the Earth..."

No, you should read this thread.

First of all, a black hole that falls to the center of the earth, wouldn't stop there, but would continue falling up on the other side, just to plunge in again, and on and on, because there's no "friction" on the black hole.

Second, there have been posted in this thread a lot of calculations of the speed at which it would gobble up matter.
Don't forget that the black hole we're talking about here IS MUCH MUCH SMALLER THAN A PROTON. As such, pressures on *atomic* level (such as in the center of the earth) matter little: the black hole travels most of the time in the empty space between nucleae.
A way to calculate the probability of hitting a nucleus (and somehow imagining that it would gobble up the entire nucleus, which is MUCH MUCH bigger than the black hole itself - which is a worst-case scenario) is done by calculating the "cross section" of the black hole and its probability to cross a nucleus on its voyages through the earth. We know its speed (just falling), and knowing the cross section and the density of nucleae, we can estimate how many nucleae it could eat per unit of time.

For a classical black hole, the calculation is done in the link provided by Pervect in this post:
http://www.physicsforums.com/showpos...4&postcount=12

for a MUCH LARGER black hole, about the size of a proton, weighting a billion tons (figure that! A black hole *the size of a proton* weights a billion tonnes ; we're talking here about black holes that weight 10 TeV or 10^(-24) kg - go figure how small it is !)

For more exotic calculations which are more severe, orion made some, and arrived at a time to eat the earth ~ 10^46 years.

All this in the following rather un-natural hypotheses:
- no Hawking radiation (which would make the black hole evaporate almost immediately)
- production of black hole EXACTLY IN THE CENTER OF GRAVITY of the collision (no remnant particles)
- very high production rate, producing billions of black holes per second.

I am not a physicist, but from what little physics I have had, and from reading threw the thread/flamewar, I dont think we have to worry about the LHC

ok, I am ripping most of the info from here: http://www.physicsforums.com/showthread.php?t=122375&page=6

        "If they were able to make a small blackhole, and it got "loose" and fell to the center of the Earth, the pressures at the Earths core would force material into it so fast that even a very small one would gobble us up very fast. I am not sure what the exact pressure is at the Earths core but it could force material through even a very small "hole" very quickly. I do agree that once it gobbled up the Earth, it would just continue to orbit the Sun, and the Moon would still orbit the blackhole as if it were the Earth..."

No, you should read this thread.

First of all, a black hole that falls to the center of the earth, wouldn't stop there, but would continue falling up on the other side, just to plunge in again, and on and on, because there's no "friction" on the black hole.

Second, there have been posted in this thread a lot of calculations of the speed at which it would gobble up matter.
Don't forget that the black hole we're talking about here IS MUCH MUCH SMALLER THAN A PROTON. As such, pressures on *atomic* level (such as in the center of the earth) matter little: the black hole travels most of the time in the empty space between nucleae.
A way to calculate the probability of hitting a nucleus (and somehow imagining that it would gobble up the entire nucleus, which is MUCH MUCH bigger than the black hole itself - which is a worst-case scenario) is done by calculating the "cross section" of the black hole and its probability to cross a nucleus on its voyages through the earth. We know its speed (just falling), and knowing the cross section and the density of nucleae, we can estimate how many nucleae it could eat per unit of time.

For a classical black hole, the calculation is done in the link provided by Pervect in this post:
http://www.physicsforums.com/showpos...4&postcount=12

for a MUCH LARGER black hole, about the size of a proton, weighting a billion tons (figure that! A black hole *the size of a proton* weights a billion tonnes ; we're talking here about black holes that weight 10 TeV or 10^(-24) kg - go figure how small it is !)

For more exotic calculations which are more severe, orion made some, and arrived at a time to eat the earth ~ 10^46 years.

All this in the following rather un-natural hypotheses:
- no Hawking radiation (which would make the black hole evaporate almost immediately)
- production of black hole EXACTLY IN THE CENTER OF GRAVITY of the collision (no remnant particles)
- very high production rate, producing billions of black holes per second.

I am not a physicist, but from what little physics I have had, and from reading threw the thread/flamewar, I dont think we have to worry about the LHC

http://www.physicsforums.com/showthread.php?t=202439

this one got pretty heated:

http://cosmicvariance.com/2007/11/16/garrett-lisis-theory-of-everything/

I too made a copy of the Alexander Mayer PDFs. I'm also very curious as to how that turned out. It sure did sound good, and had the nerve to make testable predictions.

I found this http://www.debunkers.org/ubb/Forum21/HTML/000228.html where someone named Kent Budge takes a shot at it, but doesn't really deflate it. So far as I could tell the Mayer presentations didn't claim that time goes backwards, so Budge's efforts sound like missing the point. The thread died very early, with zero mention of testing the predictions of the paper, so that's a dead end.

Threads here http://www.physicsforums.com/archive/index.php/t-110528.html and here http://www.bautforum.com/against-mainstream/37859-truth-hoax.html went on for quite some time and hammered around on it quite a bit. Both appear to have gotten hung up in Einstein-style thought experiments, with a smattering of people attempting to brand it a hoax. I notice one of those claiming hoax is now banned from the bautforum.com forum. Two physicists chimed in, one stating he was approached by Mayer in person at the AAAP in 2006 and Mayer appears to believe what he says, and one who identified himself as the experimenter who gathered some of the data Mayer references in his papers. Neither expressed an opinion on the papers. Other contributors to those threads seem to have gotten some teeth into the papers, poking holes in the thought experiment. It was esoteric enough that I'm not even sure the adversarial comments got it right. I sincerely wish that physicists would spend less time indulging in oxymoronic "thought experiments" and more time working to explain experimental data, especially when there's apparently relevant experimental data to be had in this case. An independent assessment of the alleged anomalous data and how well Mayer's theory explains it would have been nice. Wishful thinking, I suppose.

Mayer posted a statement about the revocation of his visiting scholar status at Stanford which has since dropped off the net. The Wayback Machine managed to retain a copy: http://web.archive.org/web/20060322165859/http://www.afmayer.net/pages/StanfordStory.html The statement unfortunately indulges in some paranoid remarks about established interests being threatened by his work, which puts a serious dent in his credibility. The very short Wayback Machine archive coupled with the disappearance of afmayer.net leads me to believe somebody noticed what he was up to and got him back on his meds.

A pity...

It may take someone with the minor madness of Einstein to top Einstein, but it doesn't look like Mayer managed it.

Or at least our current mathematical description of it is wrong. We cannot explain how disk galaxies spin. We cannot explain how the big bang happens without the magic fairy dust for inflation. Now we have a large wall of dark matter. Oh, and there is dark energy for galaxy acceleration. One more thing, we cannot quantize our approach to gravity.

These are the reasons I work on a rank 1 field theory for gravity. For the details, read as much of this thread as you like: http://physicsforums.com/showthread.php?t=87097 This is a LONG thread, more than 36k views, I make learn things along the way. Right now I am trying to find derive the Maxwell equations, and then the unified field theory, instead of using tensors. Quite a bit of fun. I have never had to write so many partial differential equations in my life.

Doug

Icarus, "International Journal of Solar System Studies"; unfortunately it's a subscription publication (though with some ingenuity you can find at least the abstracts of many Icarus papers through ADS; papers with preprints on arXiv are, of course, free) http://icarus.cornell.edu/. This is the best, deepest, etc resource (IMHO).

ADS Abstract service, for finding papers relevant to planetary formation (click on Physics and Geophysics Search http://adsabs.harvard.edu/ads_abstracts.html)

General, diffuse website: Astronomy Picture of the Day (APOD, most have at least some good links; not specific to planet formation though http://antwrp.gsfc.nasa.gov/apod/astropix.html)

General astronomy discussion forum (LOTS of very knowledgeable and helpful people): BAUT (http://www.bautforum.com/)

General physics discussion forum (not much on planetary formation however): Physics Forums (http://physicsforums.com/index.php)

I'll suggest some of the other resources in a later comment ...

Possibly, highschool physics has led people astray before =)
http://www.google.co.nz/search?num=100&hl=en&safe=off&q=%22resonant+frequency+of+water%22&meta=

http://www.physicsforums.com/archive/index.php/t-94766.html
"the microwave oven waves are 2450 MHz, and water has a dipole moment (negative on oxygen, slightly positive on hydrogen side), and when exposed to this electric field the water molecule tries to move to that field, but bumps into another water molecule, thus creating heat. This is not the resonant frequency of water, and the peak absorption of waves decreases as the temperature goes up because of the dielectric properties of water."

But on the other hand...
http://www.madsci.org/posts/archives/2004-11/1100632107.Ph.r.html
"The natural frequency of water is a bit more complicated, because it takes into account the mass of water molecules, the attraction between molecules, the distance between molecules, and some other stuff. Suffice it to say that most microwave ovens put out a frequency of 2.5 gigahertz. ... This isn't the lowest (also known as "primary") resonant frequency for water, but microwave manufacturers use 2.5 GHz because they want the microwave to work at any and all water temperatures. There's lots more techno-babble about resonance, matching, and the engineering of microwaves, but that'll have to be a separate question."

Perhaps what you are trying to say is that it is not the fundemental frequency, but a harmonic =). Either way. 2.5GHz is still *a* resonant frequency of water?

The problem, dear pln2bz, is in trying to parse all this in a 'somewhat semantical' way.

May I suggest, if you are really interested in understanding what's going on in the universe, that you sign up for some university courses, in plasma physics, space science, and/or astrophysics? If they are good, such courses will require you to have covered all the parts of EE that you need (so you will be able to relate 'current' to the relevant physics equations, for example), and you can get beyond trying to divine the workings of the universe from the semantical equivalent of chicken entrails or tea leaves.

Oh, and what is this 'EU Theory' (capital 't')? In which peer-reviewed science journals may one read its seminal papers?

For answers to your questions, may I recommend Physics Forums' General Astronomy section (http://www.physicsforums.com/forumdisplay.php?f=71)?

FYI, they are certainly interesting questions, but I doubt that they are 'burning' to any serious space scientist, plasma physicist, or astrophysicist. Why? If you really want to know, sign up for a PhD in one of these fields ...

As I understand it from the discussions here and here, it would be impossible with conventional rocketry, and possible but impractical with a solar-powered ion engine. The latter would take three years, during which the telescope would be unusable. That becomes prohibitive when you consider that the ISS orbit is unsuitable for observation, so after the repairs you'd need time to get the telescope back to a useful orbit. By that time the telescope would be too old.

Several alternatives are considered in those discussions, and none seem to convince those who apparently understand these matters.

Personally I'm not convinced that the telescope would be entirely unusable during an ion-engine transfer. It should be very limited in where it can point, but usable in those limited directions. And after repair you'd only need to boost it to a higher orbit. That orbit could be energetically quite close to the orbit of the ISS, and thus quickly reached. And such a plan could perhaps dramatically lengthen the lifetime of the telescope.

But I'm no expert. I may well have overlooked or misunderstood something.

You won't get any useful information by reading a Slashdot summary of a Telegraph summary of a New Scientist summary of a paper by Krauss and Dent on arxiv.org. Why not read the original paper, and decide for yourself?

http://arxiv.org/abs/0711.1821

Here's a thread on physicsforms.com about the paper, with 2 posts by Krauss (one of the authors):

http://www.physicsforums.com/showthread.php?t=199811

Doug Moen.

For those who may be interested, an interview and a couple of online discussions with Garrett Lisi participating:

http://www.physicsforums.com/showthread.php?t=179527

http://backreaction.blogspot.com/2007/08/garrett-lisis-inspiration.html

Lubos Motl is a "real" physicist? No true scotsman fallacy, anyone? Hell, do your research: Garrett Lisi has a Ph., D. in physics! http://sifter.org/~aglisi/Physics/CV.html He clearly isn't a "real" physicist, whatever that is supposed to mean (perhaps if Garrett spent more time performing intellectual masturbation and doing things like "debunking" global warming while comparing himself to Richard Feynman, then Garret would become a "real" physicist).

If anyone is interested in Garrett's reply to Motl's ad hominems, here it is: http://www.physicsforums.com/showpost.php?p=1496330&postcount=14

This is actually a relatively interesting approach, but I'm skeptical about the predictions of 20 new particles Garrett's theory makes. Ultimately it's up to experiment, as opposed to (say) a string of insults a maundering Harvard professor makes, that determines whether or not this theory is false or not.

So, here's to studying mathematics:
* My bookmarks on mathematics [~600?]
* Wikipedia mathematics portal-- recursively read through these, do a depth-five and you should be good to go.
* Synopsis of elementary results in pure and applied mathematics (G. S. Carr)-- lists 1200 theorems in mathematics, re: Ramanujan. Highly recommended.
And some math discussion forums:
* Mathematics help
* Another one
* More
* Even more
Also use irc.freenode.net #math and #not-math, as well as efnet.

That's totally wrong; any birds flying at night basically have night vision-they aren't flying blind, or they would smack into trees all the time.

There's a big difference between seeing a solid stationary object and seeing thin long pencil like objects spinning.

Secondly, birds constantly get chopped up by wind ginnies even during broad daylight.

The vast majority of birds dying from wind ginnies are because the ginnies have fast revolving, high rpm, blades. New ginnies that have larger blades and spin slower are much safer for birds:

• How to avoid killing birds with wind turbines
• But Windmills are Noisy - Do They Kill Birds?

I haven't worked on such problems myself but I'm quite sure you'll find somebody knowledgeable and willing to help on http://www.physicsforums.com/

I've found this site to be pretty good for answering any math questions I have. Your question might be a little advanced but it's worth a shot http://www.physicsforums.com/forumdisplay.php?f=4

It would fall back indeed. Thats not the problem. But it'll burn and vaporise in the process due to the friction with the atmosphere.
check this thread I just digged up via google:
http://physicsforums.com/archive/index.php/t-14993 3.html

This has been out "en anglias" since 2003 French COMETA Report

I voted for him both times. Of the two candidates, he was my preference. Doesn't mean I really like the guy. I just liked him better at the time than I did John Kerry, or Al Gore.

I actually support the war in Iraq, and support it to this day. Personally I think we should of never liberated Kuwait. Saddam Hussein was our puppet prior to that. ( http://www.physicsforums.com/archive/index.php/t-5 3783.html ) Had we left that alone, I think we'd of been much better off than we are today. We have a vast history of supporting groups to overthrow governments all over the world. We did so in Iraq, and Hussein took power. Then we sort of tried again, and he ended up killing those we half supported.

However we are where we are, and if it takes us 50 years to get that region stable, then so be it. It's been unstable for hundreds of years. 50 years is not a long time in the grand scheme of things. We stayed in many countries for many decades after WWII. We do what it takes to get the job done. We have made a commitment. We should stick with it.

That's my opinion. MOST of the country disagrees with me. That's fine. That doesn't change my opinion.

I remember something along those lines. Are you suggesting that there is more information than 6 reals and a spin? Have a look at http://www.physicsforums.com/showthread.php?t=1121 61 which talks about the wave function of the photon, but I suggest that at least in the experiment originally described in this article we are not free to consider the photon over all space. We know that the photon passed through the mask and that places serious limits on what the wave function can look like.

Vilenkin has published an interesting paper which suggests a problem with Smolin's "natural selection of life-friendly universes via black holes" theory; OTOH Smolin strikes back! Ahhh, I love it when cosmologists attack ;)

Vilenkin has published an interesting paper which suggests a problem with Smolin's "natural selection of life-friendly universes via black holes" theory; OTOH Smolin strikes back! Ahhh, I love it when cosmologists attack ;)

I've got an alternative, and it does EM too, being discussed here:

http://physicsforums.com/showthread.php?t=87097

The theory also predicts gravity waves, but the transverse modes of emission for a 4D wave are EM, and the longitudinale and scalar modes are the stuff of gravity. So GEM theory (gravity and EM) predicts that gravity waves will travel at the speed of light, but the polarization will not be transverse like GR predicts.

I think gravity MUST be viewed as a longitudinal wave, not transverse. Here's a thought experiment. You have a cup of neutrinos (see, this is a thought experiment because no such cup can be manufactured). You spill the cup. The neutrinos fall, and when they reach the floor, they keep falling, through the center of the Earth, to the other side, and in about 88 minutes, back to where they started, just to repeat the cycle again. This is a SHO (simple harmonic oscillator), with a period of 88 minutes, and a wavelength of twice the diameter of the Earth. The neutrinos are acceleration in the direction of velocity which is a defining characteristic of a longitudinal wave.

doug
TheStandUpPhysicist.com

I agree with this, but only because I have a pretty darn elegant Lagrangian. Oh, but it is OBNOXIOUS (and so should be appreciated here at Slashdot). It uses rank 1 field equations, not rank 0 like Newton (wrongo, breaks speed of light rule) nor rank 2 like general relativity (probably wrongo because the field theory cannot be quantized). The antisymmetric field strength tensor of EM is replace by an asymmetric tensor to do both gravity and EM. If you want to check out a technical discussion, it is happening here
http://physicsforums.com/showthread.php?t=87097. Yeah, I have more work to do, but you cannot fake elegance, and my proposal is not a "An acceptable 'toy' Lagrangian density function with simple analytical properties is singled out".

Later,
doug
TheStandUpPhysicist.com

I don't know if they are going to post it but I just submitted a bit to /. about how a a patent has been granted for an anti-gravity machine. The USPTO is infamous among /. readers for the idiotically obvious and obviously idiotic software and business process patents that it grants. Every time a new one of these howlers shows up here I complain that the USPTO is not doing its job and leaving the real work for the courts...where rich corporations will usually prevale. But they seem to hit new lows every month. Their own stated and court-tested policy is to refuse patents to any idea that violates known physical law. The examiner must be an idiot.

That way you will end up with a haunted computer room!

No doubt random Internet crank is right and Harvard Nobel Laureate (and everyone in that field for decades after) is wrong.

You are welcome to argue substance of the critique (the gist of which is in post-1 and post-2. The questions discussed there happen to be the topic of my masters thesis (in theoretical physics at Brown University). In the years since leaving academia to work in industry, I had followed the developments and studied the literature in this field. Basically the critique is not that Glauber is formally wrong or that Quantum Optics as a branch of applied physics is useless.

The critique is about a small sub-current among the Quantum Opticians misrepresenting their experimental results to the physicists as demonstrating some fundamental non-local effects which apparently seem to manifest, of all the various fields of physics, only in Quantum Optics. In a recent thread in PhysicsForum, Photon "Wave Collapse" Experiment (Yeah sure; AJP Sep 2004, Thorn...), I have debunked a recent QO claim (of "magic" effects observable only in QO), showing exactly how it cheats (it was a pretty blatant fraud in this case).

Generally, though, such claims do not cheat in any blatant way, but merely use the Glauber's QO terminology which has its own definitions for "counts" (which don't count) and "correlations" (which correlate these "counts"), unfamiliar to the physicists who assume that the (photo) "counts" talked about by Quantum Opticians are the actual counts shown by detectors. You can find specific details on how this "QO sleight of hand" works in a related sci.physics.research post discussing the famous 1988 Ou & Mandel experiment (which was the precursor of all modern PDC based B.I. violations experiments) allegedly showing violations of Bell Inequalities. No violations were shown either in the experiment or predicted by the QO/QED, yet the general impression physicists have about these QO experiments is that, ignoring some minor technological imperfections, the theory QO/QED predicts the violations and the experiments show them. The only valid part of such impressions among physicists, though, is that the theory (QO/QED) and the experiment indeed do agree (they agree that there are no B.I. violations).

Finally, as others have pointed out, Hydrogen merely carries the energy, you still have to generate the energy by burning fossil fuels, running nuclear reactors, setting up windmills, or some other means, and how that energy generation is done will determine the effect on the climate.

Sorry but I find it pretty silly people think it important to point out H is only an energy carrier. Fossil fuels only carry energy as well, and they take a lot longer to get the energy stored in them and are a lot dirtier getting the energy out.

As we move towards being a Type 1 civilization over the next couple hundred years we would be wise to start using Hydrogen as the storage medium as soon as possible.

Is the state of education and big oil propaganda in the world really so bad that all we get out of discussions on energy sources now is "H is only a carrier" and "H20 is a greenhouse gas"? I think we can do better than that.