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How the Ancient Egyptians (Should Have) Built the Pyramids

Roger W Moore String Theorists (202 comments)

Well, this method comes from physicists.

Clearly string theorists since, according to the summary, it creates a "dodecadron" cross-section. So having a cross-section somewhere between a 2D dodecagon and a 3D dodecahedron it clearly relies on converting the block into some multi-dimensional object with a strangely dimensioned cross-section.

5 days ago
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A Horrifying Interactive Map of Global Internet Censorship

Roger W Moore Corporate "laws" (158 comments)

Takes some seriously Orwellian doublethink to pretend copyright enforcement isn't censorship.

I think this is the result of a very narrow view point when making the map. They seem to only care about censorship by the state through direct laws. Increasingly in the US, and so some extent the rest of the western world, it is not government which restricts our rights but companies. They need to make a second map showing countries where companies have used laws to force, or bully, people into being censored through the threat of massive financial penalties.

5 days ago
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Major Delays, Revamped Beta For Credit-Card Consolidating Gadget Coin

Roger W Moore Re:Won't work with new chips (78 comments)

All the major credit card companies will be rolling out soon-to-be-mandatory chip systems for their credit cards.

They already have done several years ago. Wherever you are is about 5-6 years behind the times.

about a week ago
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The First Particle Physics Evidence of Physics Beyond the Standard Model?

Roger W Moore Re:No, there is no evidence of BSM yet (97 comments)

Actually that's not correct. The SM specified neutrino masses as zero just as it does the photon and gluon masses...or would you argue that those are free parameters as well? However I'll grant that this is not exactly a major change which is why I asked specifically about neutrino oscillations. This introduces 4 entirely new free parameters which were never included in the SM and while oscillations require that neutrinos have a mass the reverse is not true i.e. even if you give neutrinos a mass they do not have to oscillate. Hence I see no possible way that you can call this anything but new physics beyond the SM.

about a week ago
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The First Particle Physics Evidence of Physics Beyond the Standard Model?

Roger W Moore Whoa there: many corrections! (97 comments)

Since Einstein, we know gravity is the curvature of space-time. It may be represented as a force in calculations but in reality there is no force.

How about I turn that around and say that Einstein showed gravity can be modelled by the curvature of space-time but in reality it is a force? The fact of the matter is that, at a fundamental level, we have no clue what gravity is. However you can represent it very well by a spin-2, mass-less particle which couples to a particle's 4-momentum (the caveat being that you cannot make this theory work without an energy cut-off at some scale for which there is no justification). Until we solve quantum gravity we simply do not know what gravity really is but, if I were to bet, I suspect the latter is closer to the truth but needs some correction for the quantum structure of space-time which is something we have no clue about.

If gravity is not a force then do we really have a hierarchy problem?

Yes, and if anything it would be worse. The current problem comes about because we cannot scale the Higgs corrections up to the Planck-scale where we know there is new physics. If we remove that scale then we have a theory which has no upper scale limit and so should generate infinitely large corrections to the Higgs mass i.e. we go from an incredibly unlikely 1 in ~10^34 chance of the corrections giving such a light Higgs to a zero percent chance of the theory giving a light Higgs, or any Higgs with a non-infinite mass.

Obviously, if this is the case, G has nothing to do with Fermi's constant and we should not compare the two.

You are getting your 'g's and 'G's confused. In the muon g-2 experiment the 'g' is the muon's anomalous magnetic dipole moment. This is a precision test of Quantum Electrodynamics. The high order corrections to this will involve Fermi's constant (G_F) due to W and Z loops but these contributions will be incredibly small and were this any other experiment I would have said negligible but perhaps not in this case given the incredibly high precision involved. Neither of these constants have anything to do with the gravitational constant (G) nor the local acceleration due to gravity (g). So we are not comparing the two.

about two weeks ago
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The First Particle Physics Evidence of Physics Beyond the Standard Model?

Roger W Moore Re:No, there is no evidence of BSM yet (97 comments)

If there is no evidence of BSM physics yet then how would you classify neutrino oscillations?

about two weeks ago
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The First Particle Physics Evidence of Physics Beyond the Standard Model?

Roger W Moore Re:Neutrino Mass (97 comments)

As someone who has not been involved in neutrino physics (at least until very recently) I'd agree that neutrino oscillations are the first physics discovered that is beyond the Standard Model. In addition even if the g-2 experiment gives a 5 sigma discrepancy it tells you very little about what any possible new physics - to do that you have to produce the new particles directly and study them.

The corrections to the muon g-2 experiment are now so high order that they involve QCD loops. These are non-perturbative and incredibly hard to calculate correctly so all a 5 sigma discrepancy may mean is that the theorists have got the calculation wrong. Indeed this has happened before with a 3 sigma g-2 'signal' going away after an error in the theory calculation was found by the student of one of my departmental colleagues.

If I show my bias then I would say that the best chance of new physics is the new LHC run starting in March 2015 where we have almost twice the energy of the previous run and higher luminosity. This should at least double the reach of the LHC for new physics over the next 3 years. After this run any sensitivity gains to new physics will come from increasing luminosity and so take far longer to achieve, perhaps giving one more doubling of the reach but over the next ~15 years and with a lot of work involved since the high luminosity LHC upgrade has incredible background rates!

about two weeks ago
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No, a Huge Asteroid Is Not "Set To Wipe Out Life On Earth In 2880"

Roger W Moore Only a 0.0248% chance (123 comments)

Everything I've read said it's very unlikely to hit Earth in 2880. One chance in three hundred does not "likely" make.

Especially since it is actually 1 in 4,000 or 0.0248%. Still I'd actually think it would be a good thing to have the odds a lot higher, like 90%, with a lead time like this of 800+ years. To date the existential threat posed by wars have caused science to make massive advances but this has come at a huge cost of misery and death

Think of the scientific advances that could come from an existential threat that, instead of pitting us against each other, actually puts all of humanity on the same side for a change. In the past 800 years we have come from the dark ages to the internet age. If we can't get it together enough to develop the technology needed to cause a small deflection to an asteroid in the next 800 years then I'd say it was probably time for evolution to give it a second roll of the dice.

about two weeks ago
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California May Waive Environmental Rules For Tesla

Roger W Moore Best for Environment? (327 comments)

It's more that just jobs though. If this factory reduces the cost of the batteries to the point where lots more people can afford to purchase Teslas this could significantly impact air pollution in cities. While you'd need data to really know the answer this might actually be a case where the laws to protect the environment are not actually doing so.

about three weeks ago
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The Benefits of Inequality

Roger W Moore Re:Can't leave (254 comments)

I don't know about "benefits"...even the abstract says that one of the main triggers to accepting leadership was that the populace had nowhere to go, or that it was too costly to leave.

So really not much has changed. Let's face it if colonizing Mars became possible and cheap tomorrow there would be a mass exodus from the Earth as millions of people left to get away from the dodgy politicians and corporations we all have to put up with today...ironically only to end up with their own dodgy politicians and corporates a century or two later, at least if the colonization of America is anything to go by.

about three weeks ago
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Apple's Diversity Numbers: 70% Male, 55% White

Roger W Moore Flawed Study (561 comments)

In the conclusions of the study they say that "hardly any better-qualified men were passed over as a result of interventions". However, given the structure of the study, this is only true when the men are forced to compete in a competition with a deliberate sexist bias against them since they did not get to chose their group - it was assigned. Given a choice between applying for a job where the selection criteria are non-biased by gender and one where there is a clear bias which would you choose, assuming that you were the gender biased against? In addition since there is considerable competition in the workplace (for promotions, contracts etc.) it is not clear that by lowering the competition you will actually get the best people for the job. You might get people with better skills but if they cannot use these effectively in a competitive environment their overall performance may be lower.

about three weeks ago
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Larry Rosen: A Case Study In Understanding (and Enforcing) the GPL

Roger W Moore GPL more Flexible in this Situtation (191 comments)

I think it's the nightmare scenario.

True but this is not specific to GPL at all. What has happened is company A bought code from company B and company B did not have all the correct permissions and licenses under both copyright and patent law to sell that code to them. It's true that company A is now stuck because they cannot sell any product which includes that code but this would be true regardless of whether company B violated the GPL or other license.

If anything company A has more options with the GPL that they would with a proprietary license: if they lack the money to pay for a commercial license for the code for all the copies they have sold then they can choose to release their source code under the GPL as well. Note that it is an option only and not required. The code is infringing and there are two ways to fix this: pay damages and ongoing license fees or release the source code. With a commercial license you would only have the first of these options.

about three weeks ago
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I'd most like to (personally) explore:

Roger W Moore Re:Northern Canada (246 comments)

Forget the bears, unless you go in winter when things are a little nippy, it's being eaten alive by the mosquitoes and various other nasty flies that you have to worry about!

about three weeks ago
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Do Dark Matter and Dark Energy Cast Doubt On the Big Bang?

Roger W Moore QED relies on Special Relativity! (225 comments)

Irrelevant to weather it is a success or not. You seem to think that success means 'measured to within a certain accuracy'

Yes actually that is precisely what it means for a scientific theory. The aim of a scientific theory is to model the behaviour of the universe therefore the most successful theory is the one that most accurately describes the universe's behaviour.

Relativity doesnt hold a handle to that. Not even close. Aside from GPS satellites, how has our understanding of relatively improved your life?

Leaving aside that you appear to be confusing Special Relativity with General Relativity, QED requires and relies on special relativity. Hence anything which QED gives us would not be possible without special relativity. You also seem to be confusing QED with quantum mechanics in general. QED has had some useful applications but mainly in medical physics since it only applies to relativistic electrons and high energy photons e.g. PET, electron beam treatment of skin cancers etc. Special relativity also has similar applications e.g. all particle accelerators used to produce medical isotopes rely on it as well as those outside this field e.g. police radar.

about three weeks ago
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Do Dark Matter and Dark Energy Cast Doubt On the Big Bang?

Roger W Moore Re:Dark matter and dark energy (225 comments)

There is just as much evidence these criteria are true as there is for dark stuff - currently none.

Not actually correct. The bullet cluster (see Wikipedia) is extremely hard to explain without Dark Matter. This collision between two galaxies has effectively separated he normal matter from the dark matter so we observe a gravitational field bending light where there is no normal matter. Without Dark Matter you are left with the extremely hard task of trying to explain how a gravitational field can exist where there is no matter.

about three weeks ago
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Do Dark Matter and Dark Energy Cast Doubt On the Big Bang?

Roger W Moore Re:Don't ask me (225 comments)

I have no idea! You should probably ask a physicist.

You called? The answer is no and we were not really asking this question ourselves since the one of the major pieces of evidence for Dark Matter (PLANCK CMB measurement) relies on Big Bang models!

about three weeks ago
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Do Dark Matter and Dark Energy Cast Doubt On the Big Bang?

Roger W Moore Re:Oh good lord. (225 comments)

Indeed, QED is the most successful theory that man has ever formulated

No, actually that would be special relativity which has been tested to around 20+ orders of magnitude by cosmic rays as well as (arguably) tests of CPT symmetry which last time I checked (quite a while ago) was at about 18 orders of magnitude.

QED is 'only' at about 12-14 order of magnitude of accuracy (which is extremely impressive!). Indeed since QED incorporates Special Relativity it would be hard for it to be tested more accurately that SR since any test of QED is, by definition, a test of SR as well.

about three weeks ago
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Do Dark Matter and Dark Energy Cast Doubt On the Big Bang?

Roger W Moore The Bullet Cluster Makes it Unlikely (225 comments)

What if this is a similar case? Like, say, (normal) matter having gravity properties that only become noticeable on a cosmic scale?

Models like this have been considered such as MOND (MOdified Newtonian Dynamics). These models were largely shot down by the aptly named Bullet Cluster. This is a system of two galaxies colliding at a high relative speed. The gas from the smaller "bullet" cluster collides with the gas in the larger cluster causing it to slow down, heat up and emit X-rays so we can see it.

So far so go. However you can also look at the mass distribution by seeing how it distorts the light from galaxies behind the cluster (this is called gravitational lensing). This shows that most of the mass of the smaller cluster has not slowed down and is now separated from where all the gas in the cluster is located. Effectively the collision has separated the matter from the dark matter because, unlike normal matter, dark matter has a tiny cross-section for interacting with itself or other matter. This is exceedingly hard to explain by modifying the behaviour of normal matter since you are observing a gravitational field where there is no normal matter.

about three weeks ago
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Ancient Worms May Have Saved Life On Earth

Roger W Moore Re:Evolve to cope with environment (54 comments)

Increased oxygen levels can cause big problems in part because it's generally toxic, but mainly due to it's combustion enhancing properties.

It is only toxic because we have evolved to deal with air that is ~20% oxygen. Were the content 15% or 25% we would have evolved to cope with that. As for combustion enhancing firstly that does not really apply ~500 million year ago because all life was underwater where combustion is somewhat harder. Secondly the naturally combustable material today all comes from plants hence evolution would presumably have resulted in less combustable natural materials or better fire resistance because, as you point out, plants as combustable as our trees are today would rapidly die out due to fire and so would not evolve.

Unless there is some mechanism which is known to prevent evolution from being able to produce less combustable plant material I don't see the need to require a 20% oxygen atmosphere. There is also no way that lightning can "ignite the atmosphere". To get nitrogen (roughly 80% of the atmosphere) to react with oxygen requires a net input of energy so even if there were more oxygen you cannot get a runaway reaction.

about three weeks ago

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