Electrons In Camera

[Luke_K]

Thanks Ed and Luke and all…
Thats right, I thought there were scanning tunneling electron microscopes. Also remember someone working on a film outdoors and they needed a wide angle shot in very misty conditions, I thought I heard them say that the ordinary ‘photon’ cameras were not up to it and they had to get some sort of ‘electron’ camera?!. But thats by the bye.
Maybe I sounded Too literal when I said I wanted to see an electron, I suppose I should have said turn all your equations and formulas and electron properties into either a working drawing [with construction lines] or an animation of the same. The point being that if you know ‘mathematically’ that the equation or whatever you are looking at describes a, e.g. torus shaped magnetic field made of spiraling magnetic field lines through which an electric current is flowing or static in a loop, and at the center is the point particle which then, then, by reason of those things, the electron point particle must have a shape or a topology of a closed loop or whatever it is, to create all of those properties. I mean if an electron is spinning there must be a logical physical reason to sustain a spin. Is that any clearer. And all I’d like is a sketch of an actual electron topology showing all these properties and the reasons for their interacting. Is that too much to ask , especially since you guys seem to already know the description and shape of it through maths etc. Phew.

The only sketch you can get is a probability distribution. Look up the shapes of electron orbitals in an atom, and that is what the actual mathematical equation describing the electron’s behavior plots out to, just like y=x^2 plots out to a parabola. Any sketch we make of an electron isn’t really accurate, because it’s not exactly a particle, and not exactly a wave. It’s a fuzzy mathematical construct used to describe experimental observations, and that’s it.

The magnetic field of the spinning electron looks like the shape that iron filings would take when spread over a bar magnet. You know why? Because that magnetism comes from the electrons spinning! There is a net electron spin in the iron bar. The “logical physical reason” for electron spin is that the relativistic wave equations for the electron as determined by Dirac naturally produce a quantized angular momentum for the electron, known as “spin.” It’s just math, and there’s not really an everyday analogue to it.

http://stargazers.gsfc.nasa.gov/images/geospace_images/magnetism/magnet.jpg

 

[You]

The only sketch you can get is a probability distribution. Look up the shapes of electron orbitals in an atom, and that is what the actual mathematical equation describing the electron’s behavior plots out to, just like y=x^2 plots out to a parabola. Any sketch we make of an electron isn’t really accurate, because it’s not exactly a particle, and not exactly a wave. It’s a fuzzy mathematical construct used to describe experimental observations, and that’s it.

The magnetic field of the spinning electron looks like the shape that iron filings would take when spread over a bar magnet. You know why? Because that magnetism comes from the electrons spinning! There is a net electron spin in the iron bar. The “logical physical reason” for electron spin is that the relativistic wave equations for the electron as determined by Dirac naturally produce a quantized angular momentum for the electron, known as “spin.” It’s just math, and there’s not really an everyday analogue to it.

http://stargazers.gsfc.nasa.gov/images/geospace_images/magnetism/magnet.jpg

okk… if that bar magnet was an electron spinning where would the proton be, north pole south, or in between, and is there a magnetic current flowing and does it flow north to south or the other way, with regard to the proton. O, and are those magnetic lines representing perfect concentric rings like an onion or like a tightly rolled spiral like a roll of wallpaper?

 

[Luke_K]

okk… if that bar magnet was an electron spinning where would the proton be, north pole south, or in between, and is there a magnetic current flowing and does it flow north to south or the other way, with regard to the proton. O, and are those magnetic lines representing perfect concentric rings like an onion or like a tightly rolled spiral like a roll of wallpaper?

A magnetic field is a way of describing the force that a moving charge creates on other charged particles. Any moving charge creates a magnetic field. An electron spinning by itself with nothing else around it creates a magnetic field. The field created by that bar magnet has the shape of a torus (sort of, because there isn’t a hole, and the field goes out to infinity). Those lines are continuous and have no actual separation between them.

You can’t tell the north pole from that picture. If you knew which way a positively-charge particle was spinning, you could curl the fingers of your right hand in that direction and your thumb would point in the direction of the north pole. For a negative particle the direction opposite your thumb would be the north pole. As a side note, you can also use this trick to determine which way a screw will go when you turn it (righty-tighty lefty-loosey and such).

 

[You]

As a side note, you can also use this trick to determine which way a screw will go when you turn it (righty-tighty lefty-loosey and such).

---

ha thats more my speed righty tighty you

if i think of more amazing questions i will post

:tanning:

 

[You]

ok so photons and even electrons can both exist and not exist simultaneously until you measure them, at which point you see where they were as they no longer exist. ‘And there they were, gone.’
This seems to be the nature of waves. But my question now is what are waves made of, if it is a wave then it must be a wave in something, however strange it might be.
Any ideas for a wave medium for electrons/photons?

 

[GEddie]

The photon seems to be an energy wave that spreads through open space. Pure energy, since that is what it is. Not a very good answer, but our heads don’t wrap easily around physics at this level.

An electron isn’t the same as a photon. It has mass; it’s material. But it’s material that is constantly in motion: you can’t produce a can of electrons. That motion is expresed as waves. It’s part of the general fuzzyness of existence at that level.

ICXC NIKA

 

[You]

The photon seems to be an energy wave that spreads through open space. Pure energy, since that is what it is. Not a very good answer, but our heads don’t wrap easily around physics at this level.

An electron isn’t the same as a photon. It has mass; it’s material. But it’s material that is constantly in motion: you can’t produce a can of electrons. That motion is expresed as waves. It’s part of the general fuzzyness of existence at that level.

ICXC NIKA

Energy waves. They [the waves] are also discrete packets of constant size/value. It suggests to me a mechanism, [like a machine producing a discrete revolution], of an even more basic kind than the most basic particles but which produces the most basic particle as a sort of logical necessity, like a necessary structure, or a structure of effect, on a very tiny level, exists.

 

[Luke_K]

ok so photons and even electrons can both exist and not exist simultaneously until you measure them, at which point you see where they were as they no longer exist. ‘And there they were, gone.’
This seems to be the nature of waves. But my question now is what are waves made of, if it is a wave then it must be a wave in something, however strange it might be.
Any ideas for a wave medium for electrons/photons?

Haha, you’re asking the million-dollar question. Physicists originally postulated that light waves traveled through an “ether,” but abandoned that idea and accepted that they just travel through a vacuum. A light wave is a wave of electric and magnetic fields, which just exist in a vacuum without anything there (or is there?). Virtual particles are relevant to this issue, I think.

The electron wave by itself is not really understood (to my knowledge). The function describing the electron wave can be imaginary (i.e. has the imaginary number ‘i’ in it), so it only becomes physically meaningful when it is squared, making it real. The square of the wave function gives the probability distribution (where the electron most likely is). I don’t think anybody knows what an electron wave actually is.

 

[You]

Haha, you’re asking the million-dollar question. Physicists originally postulated that light waves traveled through an “ether,” but abandoned that idea and accepted that they just travel through a vacuum. A light wave is a wave of electric and magnetic fields, which just exist in a vacuum without anything there (or is there?). Virtual particles are relevant to this issue, I think.

The electron wave by itself is not really understood (to my knowledge). The function describing the electron wave can be imaginary (i.e. has the imaginary number ‘i’ in it), so it only becomes physically meaningful when it is squared, making it real. The square of the wave function gives the probability distribution (where the electron most likely is). I don’t think anybody knows what an electron wave actually is.

Any ideas why the photon always has the same values, size, speed etc.?

 

[yppop]

Any ideas why the photon always has the same values, size, speed etc.?

YOU,
I am enjoying your provocative posts .Your questions reflect a profundity that transpire any attempt to answer them in scientific terms . I believe you know more than you are letting on. Your questions are more philosophical than scientific because they are exposing the limitations (or even inadequacies ) of science in general and of the scientific method in particular in regard to science’s attempt to discover the true nature of reality.

I believe science advances not on the basis of a single methodology, but more so on the application of three general principles, one of which (its philosophical principle) is logical positivism. One of the tenets of logical positivism is: only that, which can be observed or measured has meaning. This principle restricts scientists to merely describing the relationship among “effects” without ever having to concern themselves with the “causes”. Although science is man’s most successful enterprise for “describing” reality, scientists lack the desire and mind-set for “explaining” reality.

Your question about the coherent nature of an photon is one that is generally not addressed by the scientific community. Science asks “how” does a photon act on an electron and "what’ are mathematical relationships that describe the interaction, but generally ignore the question, “why” is the photon the way that it is.

In short, science engages reality (as David Bohm implied) at an explicate level and ignores “how” things happen at the ground of reality, i.e., at an implicate level. The success of science depends on the coherence that God built into reality at the implicate level. Long before there was science; there was reality.

However in the current intellectual battle between materialists (mainly atheists and agnostics) and theists, materialists wield a mighty weapon when invoking the knowledge that science has generated. Science’s view of the reality is a palpable one; a theistic view of reality is one of faith and mystery.

What is needed for the triumph of theism is a scientific view of the ground of reality and not just a supposition that God created realty (we know that is true). We need what might be called a meta-scientific explanation of HOW God creates and operates reality. It is up to the philosopher to lead the way in this regard, it is the only approach to the discovery of the common, coherent explanation of the true nature of all the particles in the zoo, all the forces, the quantum numbers, energy, time, life, consciousness, mind and soul. Keep questioning.

Yppop

 

[Luke_K]

Any ideas why the photon always has the same values, size, speed etc.?

Well a photon doesn’t have a size, so no answer there. It always has the same speed in a vacuum because the laws of physics are the same in any inertial reference frame, and its speed is the consequence of the laws of physics (Maxwell’s equations). This is the foundation of special relativity, by the way. However, its speed does change when going through different mediums, such as glass or water, because the permittivity (how well electric forces are felt through space) or permeability (same except for magnetic forces) of those mediums are different. (The speed of light is 1/(square root of permittivity*permeability))

Photons do not always have the same values. They can have different frequencies, and their energy is given by their frequency*Planck’s constant. You tune to different frequencies of photons when you change your radio dial. Different colors are different frequencies of photons (a photon is an oscillating wave, remember).

 

[You]

YOU,
I am enjoying your provocative posts .Your questions reflect a profundity that transpire any attempt to answer them in scientific terms . I believe you know more than you are letting on. Your questions are more philosophical than scientific because they are exposing the limitations (or even inadequacies ) of science in general and of the scientific method in particular in regard to science’s attempt to discover the true nature of reality.

I believe science advances not on the basis of a single methodology, but more so on the application of three general principles, one of which (its philosophical principle) is logical positivism. One of the tenets of logical positivism is: only that, which can be observed or measured has meaning. This principle restricts scientists to merely describing the relationship among “effects” without ever having to concern themselves with the “causes”. Although science is man’s most successful enterprise for “describing” reality, scientists lack the desire and mind-set for “explaining” reality.

Your question about the coherent nature of an photon is one that is generally not addressed by the scientific community. Science asks “how” does a photon act on an electron and "what’ are mathematical relationships that describe the interaction, but generally ignore the question, “why” is the photon the way that it is.

In short, science engages reality (as David Bohm implied) at an explicate level and ignores “how” things happen at the ground of reality, i.e., at an implicate level. The success of science depends on the coherence that God built into reality at the implicate level. Long before there was science; there was reality.

However in the current intellectual battle between materialists (mainly atheists and agnostics) and theists, materialists wield a mighty weapon when invoking the knowledge that science has generated. Science’s view of the reality is a palpable one; a theistic view of reality is one of faith and mystery.

What is needed for the triumph of theism is a scientific view of the ground of reality and not just a supposition that God created realty (we know that is true). We need what might be called a meta-scientific explanation of HOW God creates and operates reality. It is up to the philosopher to lead the way in this regard, it is the only approach to the discovery of the common, coherent explanation of the true nature of all the particles in the zoo, all the forces, the quantum numbers, energy, time, life, consciousness, mind and soul. Keep questioning.

Yppop

I’m quoting your entire post because its worth it. There must be a point where we cannot see anything, ever, any longer, where matter dissolves away into an idea of matter, and the mind whose thought it is comes to the forefront.

 

[You]

Well a photon doesn’t have a size, so no answer there. It always has the same speed in a vacuum because the laws of physics are the same in any inertial reference frame, and its speed is the consequence of the laws of physics (Maxwell’s equations). This is the foundation of special relativity, by the way. However, its speed does change when going through different mediums, such as glass or water, because the permittivity (how well electric forces are felt through space) or permeability (same except for magnetic forces) of those mediums are different. (The speed of light is 1/(square root of permittivity*permeability))

Photons do not always have the same values. They can have different frequencies, and their energy is given by their frequency*Planck’s constant. You tune to different frequencies of photons when you change your radio dial. Different colors are different frequencies of photons (a photon is an oscillating wave, remember).

Right, so I could imagine that felt vibrations to sound to radio waves and light etc. as a continuous band of wave frequencies. If I hit my desk with a hammer I’ll feel the vibration as a very long wavelength wave if I hit it really fast I could hear my desk on the radio and then see it glowing, because its all waves. Could I ask a few random questions?
What is a charge, exactly? Why do protons not join together? Are protons all the same size? How fast is the universe expanding? How do quarks work? Why does a neutron have no charge? Are electric and magnetic fields basically the same thing? Any and all answers welcome.

 

[Luke_K]

Right, so I could imagine that felt vibrations to sound to radio waves and light etc. as a continuous band of wave frequencies. If I hit my desk with a hammer I’ll feel the vibration as a very long wavelength wave if I hit it really fast I could hear my desk on the radio and then see it glowing, because its all waves. Could I ask a few random questions?
What is a charge, exactly? Why do protons not join together? Are protons all the same size? How fast is the universe expanding? How do quarks work? Why does a neutron have no charge? Are electric and magnetic fields basically the same thing? Any and all answers welcome.

Charge is just a fact of the universe, like mass. We assign the word “charge” to the property that causes other particles with “charge” to interact in a specific way. Charge is what you build up when you rub your socks on the carpet. Charge is what builds up in clouds before lightning strikes. That’s all it is. The charge on an electron or proton is a fundamental charge, which is 1.6*10^-19 Coulombs (which is just an arbitrary number based on what the Coulomb is defined as).

Protons join together with neutrons via the strong force to form atomic nuclei. I believe they don’t join together completely because that would violate the Pauli exclusion principle, which says that two particles cannot occupy the same state simultaneously.

I don’t know how fast the universe is accelerating. Look it up on Wikipedia.

I don’t know how quarks work. They have color and are glued together. (Look it up.)

A neutron has no charge because the charges on the quarks which compose it add up to zero.

Electric and magnetic fields are very similar, but not exactly the same. For example, electric monopoles exist (an electron) while magnetic monopoles don’t (every magnet has a north AND south pole). An electric field can exist from a stationary charged particle, but a magnetic field only occurs when a charge is moving. According to Maxwell’s equations though, electric and magnetic fields are intimately related.

Sorry for taking so long to reply.

EDIT: This is a nice site for introductions to physics concepts: hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

 

[You]

This expansion of the universe business; would you say there is a ratio somewhere, like 2:1, or 1:1 - as in for every 1 unit distance from an observer the universe speeds up 1 unit. Something simple like that.

 

[starsmurf]

This expansion of the universe business; would you say there is a ratio somewhere, like 2:1, or 1:1 - as in for every 1 unit distance from an observer the universe speeds up 1 unit. Something simple like that.

The current value for the expansion speed is about 70 km/s/Mpc.

If you measure the distance and speed of two galaxies, A and B, if B is twice as far away as A, B will seem to be moving twice as fast as galaxy A. This is simply a result of the expansion of the universe and is not the result of some priviledged position. So there is a “ratio”.

 

[You]

The current value for the expansion speed is about 70 km/s/Mpc.

If you measure the distance and speed of two galaxies, A and B, if B is twice as far away as A, B will seem to be moving twice as fast as galaxy A. This is simply a result of the expansion of the universe and is not the result of some priviledged position. So there is a “ratio”.

Hi, you say ‘seem’, does that mean B is really moving at 70 km/s/Mpc also, or it is actually from any point of view moving at 140 km/s.Mpc.

 

[starsmurf]

Right, so I could imagine that felt vibrations to sound to radio waves and light etc. as a continuous band of wave frequencies. If I hit my desk with a hammer I’ll feel the vibration as a very long wavelength wave if I hit it really fast I could hear my desk on the radio and then see it glowing, because its all waves. Could I ask a few random questions?
What is a charge, exactly? Why do protons not join together? Are protons all the same size? How fast is the universe expanding? How do quarks work? Why does a neutron have no charge? Are electric and magnetic fields basically the same thing? Any and all answers welcome.

Sound waves are a ripple in the air, a “jiggling” of the atoms the air is made up of, that is what you hear (and feel). If you wanted your desk to emit radio waves, you would have to heat it. The waves that form light, radio waves, infra-red, ultraviolet etc are a combination of an electric wave and a magnetic wave. This is called the electromagnetic spectrum or electromagnetic radiation. All matter emits electromagnetic radiation, you and I and the things around us emit it mainly in the infra-red (“heat”), the Sun emits most of its energy in the visible part of the electromagnetic spectrum. When this light from the Sun hits the Earth’s surface, its energy is absorbed by the ground, ocean etc. In turn, the surface of the Earth gives off electromagnetic radiation, but as it is much cooler than the surface of the Sun, it radiates in the infra-red. And that is the way you produce electromagnetic radiation, it depends on the temperature of the thing giving off the radiation.

Imagine sticking a metal poker in a hot fire. At first it will give off radiation in the infra-red, we can’t see this but we can certainly feel it! Then it will glow a dull red, then a brighter orange, then a bright yellow. If the fire were hot enough and the metal able to withstand such temperatures without melting, it would continue up the spectrum to glow white, then bue-white. Astronomers can tell the surface temperature of a star, simply by examining the light it emits. So next time you look at a starry sky, you will know that the red stars are the coolest and the blue white stars the hottest.

Protons don’t join together, as in merge, because they have positive charge. If you get two bar magnets and try to force two same colored ends together, you will feel a resistance. Opposites attract, like charges repel.

All protons are the same size, they are all identical.

Quarks are fundamental particles, they come in six “flavours”, there are the up and down quarks, the top and bottom quarks and the strange and charm quarks. Protons and neutrons are made from up and down quarks. A proton has two up quarks and one down quark, a neutron has two down quarks and one up quark. The reason the proton always has the same charge and the neutron has no charge is that an up quark has +2/3 charge and a down quark has -1/3 charge. The total of the three charges must always add up to either + or - 1 or 0. The sum of the quark charges is therefore +1 for the proton and 0 for the neutron.

I hope this helps.

 

[starsmurf]

Hi, you say ‘seem’, does that mean B is really moving at 70 km/s/Mpc also, or it is actually from any point of view moving at 140 km/s.Mpc.

Sorry, I forgot to explain what the units of the expansion speed mean

Basically, it tells you that for every unit of distance you go (the Mpc bit), the speed increases by 70 kilometers (43.75 miles) per second. In astronomy/astrophysics, we don’t use that form of units to express the speed of the galaxies, just to confuse outsiders even more!

Imagine that you are in an immense movie theater. When you press a button, every seat will move one foot away from its neighbouring seat. You press the button, the seat next to you has moved one foot away, the next one over is now two feet away, the one next to that is three feet away and so on. If you were asked to measure the speed at which they were moving (say it took one second) you would measure the speed of the first seat as one foot per second, the next one as two feet per second, and the third as three feet per second. Now imagine you reset the seats. Wander over to any other seat you like. Press the button again. You will still see the same effects, the further away from you a seat is, the faster you will measure it as moving. This is not because you are the centre of the moving seats, you will see the same effect whereever you sit!

It is the same with the galaxies, we see them flying away from us because the space inbetween the galaxies, the fabric of the universe if you like, is expanding, the fabric is streching like a sheet of rubber. The further away a galaxy is, the faster it is flying away from us. You would see exactly the same effect from any other galaxy though, so it is not because we are the centre of the universe!

I hope that makes it clear, if not, please say so and I will try to explain it again.

 

[You]

Gottcha, I think. So, if you were omnipresent the expansion rate overall from your pov would be 70 km/s/Mpc. What force would one hydrogen atom exert if it hit an object while traveling at a speed of 70 km/s/Mpc? Or what force would it exert if it travelled away from an object, while tied to it, at that same speed?