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Comment Re:Gravity model (Score 1) 221

We cannot ever rightly say that general relativity is true, for it is a
scientific theory. A scientific theory is not something that can be
proved true, though it can be proved false.

In the hundred years or so since Einstein's introduction of general
relativity, no observation has produced data that would rule out general
relativity from its status as a candidate for the true description of
gravity. So in a loose sense, it still "holds true". But such wording
can be subtly confusing and, in my opinion, should be discouraged.

No experiment---not even any experiment related to quantum
mechanics---no experiment has exposed flaws in general relativity. It
is well known that general relativity and quantum mechanics are
incompatible. They cannot both be true. Still, no experiment yet
devised has been able to rule out either of those great theoretical
foundations of modern physics.

A theory of everything would need to be inconsistent, in some sense,
with either GR or with QM or with both.

Comment Re:Gravity model (Score 3, Informative) 221

It's only a very crude analogy.

That's a good point, and it should be elaborated as the proper response
to cyberchondriac.

cyberchondriac identifies the grid-bent-by-balls as "the current popular
gravity model". It is in fact a popular model, which I remember from
watching PBS even as far back as the 1970s. The good thing about this
model is that it allows one to visualize how a mass both distorts space
and moves in response to the distortion caused by another object. But
its goodness as a model of gravity ends there, in part due to
cyberchondriac's astute observation that it makes use of gravity to
explain gravity. Still, the model is not bad because it uses one aspect
of gravity (that it is nearly uniform near the surface of the Earth) to
explain a *different* aspect of gravity (that distortions caused by
multiple objects can interfere with each other and lead to motion).

In reality, it's both space *and* time that are being

Not quite. In reality, the best model that we have is general
relativity, according to which both space and time are being distorted.
But this is not to say that space and time are being distorted in
reality, because we will never know for sure what's going on in reality.
That is, a scientific theory (like general relativity) can never be
proved true, though it can be proved false. Who knows? General
relativity might be ruled out by some future experiments and replaced
with a fundamentally different view of gravity.


Submission + - The illusion of 'net neutrality'

frdmfghtr writes: IHT is running an opinion piece on 'net neutrality.' Christopher Wolf writes about the harm of net neutrality legislation, ending with:

The astonishing growth of the Internet has been due to a "hands off" policy, with the marketplace and existing laws creating the parameters rather than rigid regulatory edicts whose adverse side-effects could well be severe. Let's hope lawmakers and policymakers keep that in mind.

Submission + - StumbleUpon Buzz On Security

An anonymous reader writes: Looks like there is a major buzz (nearly 9000 thumbs-up in about a week) in the StumbleUpon community about a new Security Dashboard that first was talked about at Slashdot. The folks at CERTStation took to heart some of the beating they received at SD regarding their FLASH intensive website, and developed an AJAX/JSP based Dashboard that is truly remarkable (uses liquid screens that allow objects on the browser to move around — some flash components persist though). Add to this the dashboard now not only provides the previous threat aggregator they called Agglomerator, but also provides Critical DNS and Router statuses among a slew of other interesting bits. This is truly something. Our SD community's feedback went into a product development cycle and the company turned around something for us in quick order. I got this G2 directly from the folks at CERTStation. Maybe they should pay us royalty fees for the product testing and focus group work we did for them.

Submission + - Mice get human gene, can see color

troll -1 writes: Mice are dichromats, they have only S and M cone pigments. They don't see color too well. But now researchers at Johns Hopkins University School of Medicine and the University of California at Santa Barbara have successfully transformed their vision by introducing a single human gene into a mouse chromosome. Jeremy Nathans, one of the authors of the study, describes it as 'the same evolutionary event that happened in one of the distant ancestors of all primates and that led ultimately to the trichromatic color vision'.

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