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Comment Re:Quantum entanglement (Score 1) 165

How about communicating over extremely long distances without using extra power or keeping a directional antenna perfectly aimed?

You need a classical signal to correlate the entangled pairs, meaning you'd have to send a beam of light/radio/neutrons/whatever to the other side so they can "decode" the entangled signal.
So you actually still need the same power and directional antenna. Plus some extra equipment to handle the entangled stuff.

Comment Re:Nice trick (Score 2) 117

While you are technically correct (which is the best kind of correct), there still would be a measurable upward component, meaning the condensate would accelerate less when released from the laser trap.
This was not what they found in the experiment, instead they found differences in expansion rates of different regions of the condensate, perpendicular to the direction of gravitational acceleration, an effect caused by a different external force.

Comment Nice trick (Score 5, Informative) 117

But if it truly had a negative inertial mass, it should spontaneously move upwards, because there already is a force pulling it downwards (gravity).

As it is, it just behaves like a negative inertial mass under certain strict conditions, which is somewhat interesting, but not a ground breaking discovery. That said, go science!

Comment Re:I have always wondered... (Score 2) 114

It seems to be something non-toxic that the viruses are somehow terminally addicted to. They just suck it in until they explode.

Nope. Viruses don't have a metabolism outside of the host cell DNA/RNA. So they don't "suck", and there is no space inside the capsid (outside shell) to "suck" anything in to. From the article:

"The researchers aren't sure why, but they hypothesize that after urumin binds HA, it exerts electrostatic forces on the surface of the particle that cause the whole shell to rupture."

So the protein acts on the outside. The binding process is relatively passive, meaning the proteins just randomly move around until they bump into an HA stalk, and electrostatic charges make them stick.
Most antibodies stick the same way, but on the HA heads instead of the HA stalks. They also prevent the virus to invade a host cell by disabling the HA surface protein, but since the HA heads evolve very rapidly, it only takes one virus to escape and generate a new generation that won't bind to the antibody. The stalks evolve extremely slowly, so the new protein will keep its effectiveness over many generations of the virus.

Comment Re:Not a physicist, but curious (Score 5, Interesting) 106

If the expansion of the universe is not consistent, what causes the variation?

Einstein's equations are non-linear. The metric expansion of space-time depends on how much matter and energy there is inside that portion of space-time.

Also, quantum fluctuations in the hot dense "quantum soup" before the big bang grew into large scale structures: mass seems to be concentrated in the walls of huge bubbles, as super-clusters of galaxies, with very little mass/energy inside.

At the largest scales, the universe is still homogeneous, so on average, the expansion rate should be constant. But on the scale of the "bubbles", the differences in mass/energy density cause differences in the metric expansion of space-time.

Until recently, this was ignored in simulations, because Einstein's equations are currently impossible to solve exactly at that scale. So now they used better approximations than before, that include this varying metric expansion, and found they don't need dark energy flows to explain some observations. Instead, differences in expansion rates make it appear that some regions "flow" towards other regions, despite everything expanding.

From our point of view expansion appears to be accelerating because of this, causing us to believe that the cosmological constant Lambda (a.k.a. Dark Energy) is not zero. So now it seems they can explain a seemingly accelerating expansion with Lambda=0 using normal metric expansion.

Comment Re:Baby brain (Score 5, Interesting) 280

Reminds me of a study they did some years ago.
When asked directly, parents would claim they derived much joy and happiness from their kids.
But when asked those same parents indirectly, with some clever questions, the researchers found that the parents weren't nearly as happy as they claimed they were. Their kids caused them all kinds of stress and unhappiness.
They concluded that those parents weren't necessarily lying during the questions, but that humans probably evolved a sort of delusional condition, so that they would believe kids made them happy, and so they kept procreating. Those that didn't have these delusions, obviously didn't have as much offspring, so there was a strong selection for the condition.

Comment Re:4425*850=4 million pounds of satellite (Score 1) 121

That is an enormous amount of weight to send up.

It's also an insane amount of launches.
To get all 4425 satellites up within 7 years, they'd have to launch about 52 per month.
Even if they deploy 5 at the same time, that'd still be 10 launches per month.
Currently, they do less than that in a year.

Comment Re: critical mass (Score 1) 158

That's why I added the phone idea. You need a trusted client to do the decryption.
Don't trust your browser? Then use a dedicated device that is 100% under your control.
Or use pen and paper, since your device contains silicon you didn't create.
But make sure to close all curtains and sweep for bugs first.
If they *really* want your secrets, they'll just use the $5 wrench method anyway...

Comment Re:critical mass (Score 1) 158

Ok, I think I misread what you meant, which was the private key and the decrypted email.
So long as the decryption is done server side, there is no way to ensure the server doesn't leak this data to third parties.
So to make webmail secure, it would need to send you the message encrypted, and let you decrypt it locally with a trusted client.
It could be a plugin in your browser, or some local JavaScript that is under your control, or some local app on your phone that lets you scan the text and decrypt it on the fly.

Comment Re:critical mass (Score 1) 158

Somehow, somewhere the e-mail has to be decrypted, and both the key and the result have to be kept secure. I don't see how that can be done.

Erm, with public/private key pairs?
This is a solved problem: you exchange public keys, then encrypt all your mail to person X with the public key of person X.
Only they have the private key that can decrypt it.
When X replies tou you, they encrypt with your public key.
To authenticate your email, you can even sign it with your private key, and the other side can verify it with your public key.

Comment Re:Don't bother with the link in the summary (Score 1) 108

which means pipe smokers who inhale live as long as nonsmokers, and pipe smokers that donâ(TM)t inhale live longer than non-smokers.

This doesn't make any sense. The tobacco in pipes is sold by the same companies that make the cigarettes, so one would expect it to be similarly bad.
In fact a quick google turns up numerous studies that say just that: example graph

So pipe smokers and cigar smokers are very similar in developing cancers and mortality rates. Cigarette smokers do worse for some cancers and better for other.
As to why: I read a study years ago that concluded that smokers of "light" cigarettes developed deeper and more lethal lung cancers because they inhaled more/deeper to get the same amount of nicotine.
Cigar and pipe smokers typically inhale more shallowly, which may explain why they develop cancer of the larynx instead.

Comment Re:AI is just not ready. (Score 3, Interesting) 214

We're not there yet but this effort by Microsoft is, IMHO, as smart as a mouse.

Mice are pretty smart, I'd argue that the current AIs are at insect level of "intelligence".

What's obvious from these results is that the AI has no idea what it's looking at. This is typical for a trained neural net: it finds the best matching pattern in an image, and maps that to one of its output categories. It makes no difference between a random black and white blob, and a penguin, so long as they match the pattern.

A mouse, and true AI, will have spatial understanding. It will (intuitively) know that the images represent objects in space, and will be able to recreate a coarse 3D model of what they see. Then they will break down the scene in basic features, and identify it based on those features. It might say: hey, these blobs remind me of a penguin, but will never say that they *are* a penguin, because the blob will miss the beak and eyes and flippers and feet.

Basically, what we have now are the neural nets we already had 50 years ago, only on much faster hardware, combined with a bot and a web search engine. It's basically ELIZA on steroids, but still a long long way from actual intelligence.

Comment Re:Nah! (Score 1) 184

Some nice theories here but I'm sticking with my own pet theory: our observable universe exists entirely inside a black hole, slowly being compressed at the center across time.

Since we are in the exact center of our observable universe (per definition), that would mean we would be in the exact center of your postulated black hole.
Which would be both an astronomical coincidence (given the near infinite amount of space available), and a very bad place to be (since there should be a universe sized singularity in the center).

In other words: not a chance this is true.

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