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Physics, Astronomy & Cosmology / Is relativistic velocity a noticeable effect?

« on: 24/10/2011 11:29:57 »

I would say that if we look at a clock that "moves" away from us at speed 0.5 c, because of expansion of space, and a clock that moves away from us at speed 0.5 c, then we see the clock that "moves" is running faster than the clock that moves.

Because: "moving" can reach speeds like 5 c, while moving is always slower than 1 c.

If we look at a galaxy that is "moving" at speed 0.9 c, and moving at zero speed, then we see no Lorentz contraction in the galaxy. Or do we see?

I don't see. Gravitation of our galaxy does not make kinematic slowing of time of such very far galaxy.

It is important to remember that the Lorentz contraction is a 1-dimensional thing: it applies only in the direction of motion: towards or away. It is also the case that our observation of the extent of something is a two-dimensional thing: we can observe up, down, left, right, but not towards, away. So we have no means of directly observing whether the contraction applies or not (to the component of motion directly away from us) when we look at distant galaxies. The two dimensions of observation and the one dimension of contraction are orthogonal.

I was thinking about a large mirror to help us see what the side of a receding galaxy looks like.

But now I can see that universe is transparent enough, so we can see that receding galaxies are not packed together in the towards-away dimension.

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Physics, Astronomy & Cosmology / Would time speed up if the world stopped moving?

« on: 05/10/2011 07:33:19 »

Yes clocks would speed up if world stopped.

The well known Twin Paradox: Twin A makes a space trip, twin B stays still, after the trip twin B is older.

Just replace people with planets in the previous sentence.

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Physics, Astronomy & Cosmology / If you move away from a lightsource, will photons become 'spaced out'?

« on: 04/10/2011 06:37:43 »

Yes photons are spaced out when you are moving away from a light source.


How do photons, that are on their way, become spaced out, when you start to move away from them?

A photon behind a photon slows down more than the photon in front of it, when you are accelerating. When you stop accelerating photons move normally again.


How do photons become spaced out when you start to move before the photons exist?

Well, it's the continuous increase of distance between you and the light source that is the cause.

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Physics, Astronomy & Cosmology / Is relativistic velocity a noticeable effect?

« on: 27/09/2011 18:05:27 »

I would say that if we look at a clock that "moves" away from us at speed 0.5 c, because of expansion of space, and a clock that moves away from us at speed 0.5 c, then we see the clock that "moves" is running faster than the clock that moves.

Because: "moving" can reach speeds like 5 c, while moving is always slower than 1 c.

If we look at a galaxy that is "moving" at speed 0.9 c, and moving at zero speed, then we see no Lorentz contraction in the galaxy. Or do we see?

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Physics, Astronomy & Cosmology / Geodesics around a planet

« on: 25/09/2011 02:20:38 »

Here are 3 planets, lined up on a straight line, in flat (not curved) space:

O   O   O

On the leftmost planet stands a person, with a laser gun, his task is to shoot a laser beam to the rightmost planet. As the planets have quite strong gravity fields, the shooter must point the gun a little bit upwards, then the beam takes a curved path to he rightmost planet.



Now, let's pull a wire from the leftmost planet to the rightmost planet, like this:
And let's make it an extremely tight wire.
__________
O   O    O



A person near the wire will say that the wire sags just a little bit, because of gravity.

A person observing the wire from far away position says that the wire arches upwards, away from the planets. (same kind of arch as the path of the laser beam)


So, watching the wire or the beam a distant observer can perhaps get some kind of idea how space is curved near the planets.

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New Theories / Why wouldn't this work? (perpetuum motion)

« on: 21/06/2011 04:16:09 »

Hello everyone.

There's an idea that bugs me for last few years. I've tried consulting few PhDs and got no answers, and I have no materials to do this experiment on my own.
I know that this device shouldn't work, but I have no idea why.

Let's say that we have a charged capacitor. Let's use most simple version of capacitor - two parallel conductive plates that have same dimensions and we charge those plates to say... 100V (doesn't matter, really).

Place closed coil of wire around one plate. The coil should enter capacitor space near -100V charged plate, and exit capacitor space near +100V charged plate, so there should be nice difference in potential energy of free electrons in coil that are near +100V plate and those that are close to -100V plate.

In theory, capacitor energy is defined only by its voltage levels and capacitance. Since capacitor is charged, and disconnected, the voltage levels should stay the same, and since it is rigidly built, it should not change it's capacity.

Electric field should appear as soon as we charge the capacitor, and it should exist only between capacitor plates. This field should start moving free electrons in coil thus producing a current in coil circuit. Now, if we place resistor in coil circuit the current generated in coil should generate heat in resistor transforming electrical energy in heat.
The question is obvious. Only energy that we provided to this system was energy used to charge capacitor, and now we have heat constantly generated by current passing through resistor, and capacitor should maintain its voltage levels...

So, if anyone knows how capacitor will lose it's energy, please reply. Don't bother with imperfection of regular capacitor, I know it will "run dry" by itself. I want to know how it loses its energy when it transfers it to electrons in the coil.

Thank you!
PS Please excuse any grammatical and spelling mistakes that I made.

Think about it this way:

If lot of electrons are packed into a metal plate, then the electrons want to move away from the plate, because same charges repel.

If some positively charged object is brought near the metal plate, then electrons don't want to move away from the metal plate as much as before, because opposite charges attract.

And that's how capacitors work.

Now all we need to understand is that the aforementioned urge of the charges to leave the plate of the capacitor is what we call the voltage of the capacitor, and that the voltage diminishes whenever any opposite charges move towards the capacitor plate.

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Physics, Astronomy & Cosmology / How can a photon interfere with itself while in a parallel universe?

« on: 18/03/2011 03:27:07 »

Greetings,

This one is really theoretical. In the Young Double-Slit experiment, light that passes through two small slits interferes with itself and creates an interference pattern on the other side (wave-like properties). However, if only one photon is emitted at a time, an interference pattern will form. It seems the photon has gone through both slits at the same time. Richard Feynman and others postulate that the photon traverses multiple universes (dimensions) to pass through both slits and interfere with itself on the other side. How can a photon interfere with itself while in a parallel universe? [?]

 [] Thank you,

John

When photon(s) hit a black screen, the screen plus the photon(s) scatter into trillion different universes. There is a pattern in this scattering, that's the interference pattern. 

That was a very incomplete explanation.

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Physics, Astronomy & Cosmology / Why does an object require infinite energy to travel at a finite speed?

« on: 18/03/2011 02:45:53 »

Not yet. Ironically, I was not responsible for shrinking Phractality's post!

I'm sorry. I'm just frustrated because there isn't too much good scientific discussion around. 

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New Theories / Is this short story scientically correct?

« on: 17/03/2011 11:50:05 »

Actually I know it's perfectly correct.

I just pretended to ask a question.

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Physics, Astronomy & Cosmology / Why does an object require infinite energy to travel at a finite speed?

« on: 17/03/2011 11:33:30 »

Oh, that's one I can answer!

You'll find the AUP here http://www.thenakedscientists.com/forum/index.php?topic=8535.msg99453#msg99453

Pay particular attention to Bullet 5.

"The site is not for evangelising your own pet theory.  It is perfectly acceptable that you should post your own theory up for discussion, but if all you want to do is promote your own idea and are not inviting critical debate about it, then that will not be acceptable.

Well I was going to say something critical. But the long post has been
deleted. Without a word of explanation.

Geezer you are an asshole.

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New Theories / Is this short story scientically correct?

« on: 16/03/2011 18:26:15 »

Lifting your computer from the floor onto the table gives you an advantage in an on-line computer game: You have a faster computer.

This faster computer draws more current from the wall socket. It uses more energy to flip a transistor one time, and the frequency of transistor flipping is higher.

What if the computer is a laptop running on battery? Whether the laptop is on the floor, or on the table, the same amount of computing can be done with the energy of the battery.

So, lifting a laptop must increase the energy of the laptop battery.

What if the laptop has purely optical circuits, and the "battery" of this laptop is a mirrored box filled with photons?

Well, obviously lifting this laptop must increase the energy of each photon.

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Physics, Astronomy & Cosmology / Is this youtube videeo scientifically correct?

« on: 12/03/2011 11:31:04 »

Speeds that the rods reach are relativistic

http://www.youtube.com/watch?v=oqa3HYkg5no

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Physics, Astronomy & Cosmology / Why does an object require infinite energy to travel at a finite speed?

« on: 11/03/2011 10:13:11 »

Frames are kind of squeezed together, when you look at the frames from a distant frame.
Here "frame" means "frame of reference".

For example: Bullet is in a frame only 1 m/s apart from the frame of the rifle that shot the bullet, when you are looking at this shooting event from a frame that is 299999999 m/s apart from the frame where the shooting event happens. 

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Physics, Astronomy & Cosmology / Why does heating increase mass?

« on: 30/01/2011 14:13:17 »

Always people turn hostile when I'm showing off my superior physics skills []

1:  A particle accelerator

2: one proton  .... one electron here further away


1 and 2 are the same, I mean there is no fundamental difference. Electron gains mass
in both cases.

 

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Physics, Astronomy & Cosmology / Why does heating increase mass?

« on: 29/01/2011 17:02:35 »

When electron falls into proton, mass of electron INCREASES, mass of proton DECREASES, and vacuum's em-field becomes exited and its mass INCREASES.

Which movie is it?  []

I don't like that comment. Electron in an atom actually has quite a lot
speed.

Note that when an electron and a proton fuse into an atom the electron and the
proton move through a voltage drop that is more like 10000 V than 13.6 V.

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Physics, Astronomy & Cosmology / Why does heating increase mass?

« on: 29/01/2011 05:44:33 »

When small mass falls into large mass, small mass loses some energy, which energy goes into the large mass.

Here is derivation:

Case 1:
Equal masses fall into each other, both heat up. The heat is responsible for some of
the mass of the objects.

Case 2:
Two objects with equal masses but non-equal heat capacities fall into each other,
the object with larger heat capacity will be responsible for bigger part of the
mass of the 2-object system.

Case 3:
There are 2 objects with equal mass, one object is ground to small pieces, and
slowly poured onto the other object. The grinding and slow pouring of object number
one probably does not inspire object number 2 to donate any extra energy to the
ground object. So gravitational energy transfer in case 3 is same as it is
in case 2, and thermodynamical energy transfer in case 3 is same as it is in case 2.
(the ground object is heating the other object)

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Physics, Astronomy & Cosmology / Why does heating increase mass?

« on: 29/01/2011 00:55:54 »

When electron falls into proton, mass of electron INCREASES, mass of proton DECREASES, and vacuum's em-field becomes exited and its mass INCREASES.

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Physics, Astronomy & Cosmology / Why does heating increase mass?

« on: 29/01/2011 00:50:50 »

Oh yes, they say that photons curve space-time with their momentum.

That depends, according to the Bonnor beam model. But there are several views to that one. Also, as a photon only can be shown in its interaction, where do those beams 'exist'?

Photon obviously curves space-time if million photons and trillion
massive objects say it does, and some very special and rare photons
say it doesn't.

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Physics, Astronomy & Cosmology / Why does heating increase mass?

« on: 28/01/2011 04:10:24 »

If photons create weight do they lose energy for it?

No, weighing does not use energy, as far as I understand.

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Physics, Astronomy & Cosmology / Why does heating increase mass?

« on: 27/01/2011 17:20:08 »

weight≠mass 

You're flogging a dead horse - photons have many properties, states and characteristics; mass is not one of them. 

Everyone has a right to have their own opinion, I guess.

But what would impress me would be someone showing me a case where any kind of mass measuring device measures a closed box changing its mass.

Does any mass measuring device exist?