Ask a physicist anything. (5)

[leftrightleftrightleft]

When two particles are created (e.g., a high-energy photon (gamma ray) creating an electron and a positron), those two particles are forever entangled with one another. Quantum mechanically, we cannot describe one without mentioning the other. Such particles created in pairs are how we generate entangled particles.

Thanks for the thorough reply.

So its only when particles are created at the same instant that they are entangled? Because I heard some rumor that every particle in my body is theoretically entangled with other particles potentially light years away. I suppose this is just one of many QM myths?

This still leaves the lingering question: if you entangle two particles and then make one of the "do" something, does the information that you've sent to the one get transmitted instantaneously to the other, regardless of the distance of separation?

It looks complicated, but there are thousands of scientists working at the LHC who will carefully analyse this information. Sufficient data is collected by the machines that we can work out which lines refer to which particles - and any anomalous particles will be evidence of brand new physics!

And what, if I am ask bluntly, is the point of all this? Can the discovery of the Higgs Boson be applied to any meaningful technology or task? Or do scientists just not know and its one of those things that might have unknown applications in the future?

Also, in the book I mentioned in my first post, the authors talked about the search for the Higgs Boson which they claimed would be the "origin of mass". They then spent the next several paragraphs talking about how much the Higgs Boson would weigh. Buuuut, if the Higgs Boson is the source of mass, how can it also have mass itself?

 

[Wiccan_Child]

Thanks for the thorough reply.

So its only when particles are created at the same instant that they are entangled? Because I heard some rumor that every particle in my body is theoretically entangled with other particles potentially light years away. I suppose this is just one of many QM myths?

Yea, sounds like quantum mysticism to me. Pay no attention it

This still leaves the lingering question: if you entangle two particles and then make one of the "do" something, does the information that you've sent to the one get transmitted instantaneously to the other, regardless of the distance of separation?

Sadly not. There may be ways to exploit this instantaneousness, but not without reworking out understanding of entanglement.

And what, if I am ask bluntly, is the point of all this? Can the discovery of the Higgs Boson be applied to any meaningful technology or task? Or do scientists just not know and its one of those things that might have unknown applications in the future?

Indeed. Theoretical physics is done for its own sake, rarely with any real technological goal in mind, because it is the investigation into new physics (as opposed to, say, applying established QM into circuitry).

The wise government realises the benefit in letting its scientists investigate theory for its own sake, because it often leads to monumental changes in technology. Look at what the study of electromagnetism has given us - the computer is, arguably, the apex of that study, and our world has been fundamentally transformed.

So who knows. Maybe the discovery of the Higgs will usher in the age of mass manipulation, allowing us to create artificial gravity, to life 'heavy' loads effortlessly, etc. Architecture, transportation, space flight, everything would be as fundamentally altered as if we had just invented the wheel.

Also, in the book I mentioned in my first post, the authors talked about the search for the Higgs Boson which they claimed would be the "origin of mass". They then spent the next several paragraphs talking about how much the Higgs Boson would weigh. Buuuut, if the Higgs Boson is the source of mass, how can it also have mass itself?

Because of how the Higgs confers mass to particles. Basically, imagine a quark streaming through space at lightspeed. It is, technically, massless. But there are these Higgs all around, literally everywhere, and they are slightly attracted to the quark. So they bump into the quark, slowing it down slightly, making it harder to accelerate, etc - in other words, the quark behaves like it has mass.

It doesn't have mass, it's just the Higgs artificially slowing it down.

So what if the Higgs interact with each other, slowing each other down? That would mean each Higgs has a 'mass' too.

 

[mzungu]

Why is it called "beauty"?

Because to one who has an affinity for technology it truly is a beautiful beast! Like they say "beauty is in the eyes of the beholder"

 

[mzungu]

The wise government realises the benefit in letting its scientists investigate theory for its own sake, because it often leads to monumental changes in technology. Look at what the study of electromagnetism has given us - the computer is, arguably, the apex of that study, and our world has been fundamentally transformed.

I want my Quantum Computer

 

[leftrightleftrightleft]

Sadly not. There may be ways to exploit this instantaneousness, but not without reworking out understanding of entanglement.

Doesn't this contradict the notion of "something" moving faster than the speed of light? How is this entanglement "information" sent? Or how the two particles "know" they are entangled?

Because of how the Higgs confers mass to particles. Basically, imagine a quark streaming through space at lightspeed. It is, technically, massless. But there are these Higgs all around, literally everywhere, and they are slightly attracted to the quark. So they bump into the quark, slowing it down slightly, making it harder to accelerate, etc - in other words, the quark behaves like it has mass.

It doesn't have mass, it's just the Higgs artificially slowing it down.

So what if the Higgs interact with each other, slowing each other down? That would mean each Higgs has a 'mass' too.

Interesting. So all particles are naturally meant to be massless and travel at the speed of light? Has it been considered why photons seem to have escaped interaction with this theoretical Higgs particle?

 

[leftrightleftrightleft]

Also, do you know anything about tachyons?

 

[Wiccan_Child]

Doesn't this contradict the notion of "something" moving faster than the speed of light?

The speed limit of the universe only really applies to real things, like particles, and ostensibly not 'information', and it only means that particles can't accelerate faster than the speed of light. But you're right, entanglement causes a headache for relativity, and I think it's one of those cases where QM and GR clash - and it seems QM is winning.

How is this entanglement "information" sent? Or how the two particles "know" they are entangled?

In essence, because measuring one tells us something about the other. For instance, one of the pair must be spin-up, and the other spin-down. If we measure particle A to be spin-up, then we know that particle B must therefore be spin-down. In theory, we could peek at particle B and see when it suddenly goes from being in a state of quantum indeterminance to being in a state of spin-down - thus transmitting information instantaneously.

But the problem is twofold: how do we 'peek' at a particle (in essence measuring its spin without actually measuring it), and determining whether particle B wasn't in a state of spin-down all along.

Interesting. So all particles are naturally meant to be massless and travel at the speed of light? Has it been considered why photons seem to have escaped interaction with this theoretical Higgs particle?

I'm afraid you're leaving the bounds of my knowledge here Perhaps photons simply don't interact with the Higgs for the same reason an electrically neutral particle doesn't interact with EM fields, or neutrinos flit through the entire Earth without (hardly) interacting.

Also, do you know anything about tachyons?

A tachyon is any particle that travels faster than light. This isn't technically impossible, since particles can't accelerate past lightspeed - but there could be particles which always travel faster than lightspeed, just as photons travel at lightspeed.

According to GR, such particles would propagate backwards through time, but peculiarly not causing havoc with causality. Funny buggers then tachyons.

 

[Steffenfield]

If I dropped a running blow dryer in the toilet, how far do you think that electrical discharge would travel down the pipes?

Is it possible that it would emerge back up, say to my neighbor's toilet?

Thanks for letting us ask weird questions here.

 

[Nabobalis]

If I dropped a running blow dryer in the toilet, how far do you think that electrical discharge would travel down the pipes?

Is it possible that it would emerge back up, say to my neighbor's toilet?

Thanks for letting us ask weird questions here.

Are you planning to murder someone?

 

[Wiccan_Child]

If I dropped a running blow dryer in the toilet, how far do you think that electrical discharge would travel down the pipes?

Is it possible that it would emerge back up, say to my neighbor's toilet?

Not a chance, it probably wouldn't travel very far at all. Electrocution is only really a problem with water if you're connected to the electronics by water, and that connection can't be very long at all. So your toilet is quite fine!

Thanks for letting us ask weird questions here.

Ah, I learn from the best:

YouTube - worldview's Channel

 

[Steffenfield]

Okay.

So, um, how does one have toilet water continuously hooked up to electronics in a person's home?

It's, ah, a class project, yeah, that's it.

 

[mzungu]

Okay.

So, um, how does one have toilet water continuously hooked up to electronics in a person's home?

It's, ah, a class project, yeah, that's it.

Electricity will always take the route of least resistance. If the neighbours toilet is the easiest route to earth or to the neutral conduit and the earth or neutral is hooked to the feet and the bottom is touching the water then yes your neighbour will suffer a shock!

 

[AV1611VET]

Why do ice cubes start to disappear if left in the freezer untouched?

 

[Wiccan_Child]

Who do ice cubes start to disappear if left in the freezer untouched?

I didn't know they did. They could be evaporating like a normal puddle left in the Sun, albeit much much slower... either that or someone's eating them

 

[Chesterton]

Why do ice cubes start to disappear if left in the freezer untouched?

Wholesale Appliances - Quality Appliances At Sale Prices

 

[Frumious Bandersnatch]

Why do ice cubes start to disappear if left in the freezer untouched?

Sublimation.
http://en.wikipedia.org/wiki/Sublimation_(phase_transition)

 

[TheReasoner]

I got an email from a friend of mine who is interested, but not very well versed, in science. He's a creationist - alas, but that's the way it goes with excessive influence from the wrong groups across the pond.

Regardless, the message was a question about relativity, and I thought the site he quoted was so *ahem* "interesting" I thought I'd post it here.

First off, his quote from the site in question:

When Einstein had trouble explaining his new theory of gravitation to the public, someone came up with a picture of a rubber membrane with a dimple under the large mass (above). Everyone nodded, as if they understood. No one suggested that the "real gravity" was making the mass sink into the rubber membrane. BUT, if the image had been turned on edge (right), everyone would have asked, "What is the force pushing the mass to the right?" and no one (except a mathemathican) would have agreed with this lame theory.

The site: 21st Century Ideas

What do you think? I think it's.. Errr... A little tin-foil-hat-ish. To be kind.

 

[mzungu]

Why do ice cubes start to disappear if left in the freezer untouched?

Oh dear you have one of these in your freezer Quick call the Mythbusters

 

[Supreme]

Did you know WC, that the UK has 1% of the global population, yet produces 12% of the world's scientists?

 

[1611AV]

Why is the universe expanding at a faster rate than it was in the past?