True -- they don't actually meet, but their proximity is the sole reason for pluto's demotion since that is the only thing different in the definition of planet versus dwarf planet:
From the IAU:
(2) A "dwarf planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape2, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.
The problem is that the definition they came up with is still open to interpretation.
The official definition from the IAU website:
(1) A "planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.
They demote pluto because it hasn't cleared the neighborhood of its orbit because its orbit intersects the orbit of Neptune. But doesn't this necessarily mean that Neptune has not cleared its neighborhood and therefore is also not a planet?
What does clearing the neighborhood mean? To me it suggests the planet should have no moons either?
If you are going to make a big deal and change the definition of something like this you should put a heck of a lot of thought into creating a definition that is objective and not open to interpretation.
I agree. It would have been nice if the article compared what they have done here with what is already been done by commerical quantum key ditribution (www.magiqtech.com).
It is not clear from the article what is actually the new breakthrough...
Personally I'd love to see us progress to the point where it was possible to grow just the meat itself without the animal.
There is a great 'speculative fiction' novel by Margaret Atwood called Oryx and Crake where they have genetically engineered chicken to be just masses of flesh that you can 'harvest' meat from. They have no brain or heads...just the necessary organs to let the meat grow.
They call them Chicki-knobs, which is still my favourite word to describe things like chicken McNuggets and Big Macs.
She also wrote about pigoons, which are fictional transgenic creatures that look much like domestic pigs, but their DNA has been spliced with human genetic information and they have been engineered to grow multiple organs for transplants.
In the past governments have claimed services such as Google Earth compromise national security by making it possible to see aerial details of restricted areas/buildings that people would not have as easy access to without the service.
I think that is bollocks since such details are always available from other sources...
You could look into Octave, which is an OS version of MATLAB released under GPL. You could either use it directly or look into the source for some helpful ideas.
One would hope that if you were planning on giving a speech about the internet that you would either pay an aide to sit you down and brief you on it... "
Unfortunately, informing senators about things of this nature and how the bills would affect their constituencies is the job of lobbysists, which seem to have lost sight of their real jobs recently...
There is a difference between seeing individual atoms move in ferroelectric domain inversion and 'investigating chemical reactions'. Femtosecond laser spectroscopy can really only tell you something about the atomic makeup of a sample and how it changes on a femtosecond timescale...not so much seeing atoms of the sample moving around. So, this is an important step and not so much 'BS' as you put it.
I agree with you to some extent, and I think a lot of the problem comes from scientific journalism. The Nature paper itself makes no such claims about a computer running better off -- but there is a quote from the author at the end of the New Scientist article that implies it. It is the slashdot title that used those words, the New Scientist article implied it, and the Nature article makes it clear that it is 'quantum on and off' by using dirac notation. The scientists themselves I think are innocent.
I have seen this numerous times (including in the case of the teleportation experiments) and the main problem is trying to explain things about the quantum world to people that don't have a physics degree. One is forced to use 'classical language' for these tasks. Should we not talk about electrons with spin? They are not spinning in the classical manner, but we talk about the spin of electrons all the time and layman science-writing talks of this phenomenon in a very classical manner.
The language may confuse laypeople, as you say, but the Nature article was intended for scientists...not them. They have to use the language that exists and then the New Scientist writers should clarify the meaning for the laymen.
You say, "An honest scientist would say, 'The computer runs better when it is quantum-off'", and this is precisely what the scientists did in the Nature article. The Slashdot poster, Zonk, who made the title of the post -- I agree...call Bullshit.
First of all: Profit? These are university physicists, not a company trying to trick you into buying something. The most they profit will be a pat on the back from the physics community.
Second: you clearly don't understand the experiment, so why accuse the authors of 'bullshit marketing-speak'? 'On and Off' are not necesarily classical notions; the method to implement on and off is quite simple -- you just use a beamsplitter.
You also seem to have the impression that just because two photons are entangled, that they somehow talk to one another nonlocally. Well, this does not happen in this experiment because there is only ever a single photon, which has an amplitude to go towards the computer ('on') or not towards it ('off'). There is no way for the amplitude for 'on' to communicate with the amplitude for 'off'.
The point of the experiment is that by having the computer not run you can still gain information about which element of the database is the marked element. This effect can be enhanced by utilizing the quantum Zeno effect, which they describe in the Nature article and the supplementary material -- though they don't seem to perform the experiment with the Zeno enhancement, which is a shame.
As for teleportation: you need words to describe the situation you produce. I think the word teleportation is a perfectly good word to describe the effect of transferring the quantum state of a photon instantaneously. I think it is wrong to assume the Star Trek definition of transportation is the correct one. If you are confused by what experiments are actually showing: read the article or ask a physicist.
I wouldn't call this an old result -- optical quantum computation is rarely performed, let alone running a quantum computer in a superposition of on and off. Plus, Nature does not usually publish old results.
Yes, perhaps this was theoretically been worked out in the past; yes, interaction-free measurements have been done before; but this is definitely new.
No, because if someone were to perform a QND on the photon carrying the information, it would would introduce noise in the conjugate variable which the receiver would be able to detect as an eavesdropper.
QND is essentially defined as introducing no noise into the variable you measure, which doesn't violate Heisenberg because all of the noise is introduced into the conjugate variable.
Classical correlations are not suprising, and your 2 rocket experiment is the perfect example of a classical correlation.
The thing you can do with quantum variables (like spin, polarisation, whatever you are using) that you can't do with classical quantities is measure in a different 'basis'. (It is essentially the same as doing a basis change in linear algebra: if you write down a vector in different bases, the projecting the vector onto the basis vectors will give you different probablilities.)
Now in the quantum experiment the weird thing you can do is wait until the last possible moment to choose which basis you are going to use (i.e. wait until the photons have been created and are in some definite state) -- then you can try to 'trick' the photons. But, if you DO this experiment, the correlations always exist, no matter what basis you choose.
This experiment is the basis for Bell's inequalities, which prove that a 'local hidden variable' theory can NOT explain these correlations.
Re: 'there is no way of measuring where a given particle is'
That is not true: There is a way to measure...but when you do measure where the particle is you 'collapse the wavefunction' and you localise the particle to a particular location. But if you DON'T measure the location of the particle, the interference pattern that arises can only be explained if SOMETHING was at two places at once (this something is the probability amplitude for that particle).
No money is made from Gmail. It is all made through Adsense, which is everywhere in Google products (maps, search, groups, froogle, etc.). So, on its own Gmail makes nothing and Adsense makes everything.
My question is:
Is this company claiming rights to the way Gmail works or just to the name?
I was a test subject for a physics professor here at the University of Oxford that developed the use of the same type of fluid lens technology for low cost eyeglasses (they cost about a tenner). They had plans to take them to 3rd world countries to provide spectacles for people who couldn't normally afford it.
Slashdot Mirror
You know it wasn't actually a war, right?
From the IAU:
They demote pluto because it hasn't cleared the neighborhood of its orbit because its orbit intersects the orbit of Neptune. But doesn't this necessarily mean that Neptune has not cleared its neighborhood and therefore is also not a planet?
What does clearing the neighborhood mean? To me it suggests the planet should have no moons either?
If you are going to make a big deal and change the definition of something like this you should put a heck of a lot of thought into creating a definition that is objective and not open to interpretation.
I agree. It would have been nice if the article compared what they have done here with what is already been done by commerical quantum key ditribution (www.magiqtech.com). It is not clear from the article what is actually the new breakthrough...
There is a great 'speculative fiction' novel by Margaret Atwood called Oryx and Crake where they have genetically engineered chicken to be just masses of flesh that you can 'harvest' meat from. They have no brain or heads...just the necessary organs to let the meat grow.
They call them Chicki-knobs, which is still my favourite word to describe things like chicken McNuggets and Big Macs.
She also wrote about pigoons, which are fictional transgenic creatures that look much like domestic pigs, but their DNA has been spliced with human genetic information and they have been engineered to grow multiple organs for transplants.
A or B = True
~A = True
Therefore, B=True
In the past governments have claimed services such as Google Earth compromise national security by making it possible to see aerial details of restricted areas/buildings that people would not have as easy access to without the service. I think that is bollocks since such details are always available from other sources...
You could look into Octave, which is an OS version of MATLAB released under GPL. You could either use it directly or look into the source for some helpful ideas.
Unfortunately, informing senators about things of this nature and how the bills would affect their constituencies is the job of lobbysists, which seem to have lost sight of their real jobs recently...
There is a difference between seeing individual atoms move in ferroelectric domain inversion and 'investigating chemical reactions'. Femtosecond laser spectroscopy can really only tell you something about the atomic makeup of a sample and how it changes on a femtosecond timescale...not so much seeing atoms of the sample moving around. So, this is an important step and not so much 'BS' as you put it.
I have seen this numerous times (including in the case of the teleportation experiments) and the main problem is trying to explain things about the quantum world to people that don't have a physics degree. One is forced to use 'classical language' for these tasks. Should we not talk about electrons with spin? They are not spinning in the classical manner, but we talk about the spin of electrons all the time and layman science-writing talks of this phenomenon in a very classical manner.
The language may confuse laypeople, as you say, but the Nature article was intended for scientists...not them. They have to use the language that exists and then the New Scientist writers should clarify the meaning for the laymen.
You say, "An honest scientist would say, 'The computer runs better when it is quantum-off'", and this is precisely what the scientists did in the Nature article. The Slashdot poster, Zonk, who made the title of the post -- I agree...call Bullshit.
Second: you clearly don't understand the experiment, so why accuse the authors of 'bullshit marketing-speak'? 'On and Off' are not necesarily classical notions; the method to implement on and off is quite simple -- you just use a beamsplitter.
You also seem to have the impression that just because two photons are entangled, that they somehow talk to one another nonlocally. Well, this does not happen in this experiment because there is only ever a single photon, which has an amplitude to go towards the computer ('on') or not towards it ('off'). There is no way for the amplitude for 'on' to communicate with the amplitude for 'off'.
The point of the experiment is that by having the computer not run you can still gain information about which element of the database is the marked element. This effect can be enhanced by utilizing the quantum Zeno effect, which they describe in the Nature article and the supplementary material -- though they don't seem to perform the experiment with the Zeno enhancement, which is a shame.
As for teleportation: you need words to describe the situation you produce. I think the word teleportation is a perfectly good word to describe the effect of transferring the quantum state of a photon instantaneously. I think it is wrong to assume the Star Trek definition of transportation is the correct one. If you are confused by what experiments are actually showing: read the article or ask a physicist.
Yes, perhaps this was theoretically been worked out in the past; yes, interaction-free measurements have been done before; but this is definitely new.
QND is essentially defined as introducing no noise into the variable you measure, which doesn't violate Heisenberg because all of the noise is introduced into the conjugate variable.
Classical correlations are not suprising, and your 2 rocket experiment is the perfect example of a classical correlation.
The thing you can do with quantum variables (like spin, polarisation, whatever you are using) that you can't do with classical quantities is measure in a different 'basis'. (It is essentially the same as doing a basis change in linear algebra: if you write down a vector in different bases, the projecting the vector onto the basis vectors will give you different probablilities.)
Now in the quantum experiment the weird thing you can do is wait until the last possible moment to choose which basis you are going to use (i.e. wait until the photons have been created and are in some definite state) -- then you can try to 'trick' the photons. But, if you DO this experiment, the correlations always exist, no matter what basis you choose.
This experiment is the basis for Bell's inequalities, which prove that a 'local hidden variable' theory can NOT explain these correlations.
Re: 'there is no way of measuring where a given particle is'
That is not true: There is a way to measure...but when you do measure where the particle is you 'collapse the wavefunction' and you localise the particle to a particular location. But if you DON'T measure the location of the particle, the interference pattern that arises can only be explained if SOMETHING was at two places at once (this something is the probability amplitude for that particle).
My question is:
Is this company claiming rights to the way Gmail works or just to the name?
(...with poor spelling of the word 'their')
http://hardware.slashdot.org/comments.pl?sid=15928 1&cid=13339898
See there webpage here.