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#76 2014-05-19 17:20:23

SpaceNut
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From: New Hampshire
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Re: Relativity of light - light at light speed

Physicists: We Know How to Turn Light Into Matter And it could happen within a year, they say

Two particles of light (photons) will be smashed together to create an electron-positron pair, known as a Breit-Wheeler pair. First a stream of electrons will be fired into a slab of gold, creating a high-energy photon beam; then, a high-energy laser will be fired into a gold can called a hohlraum, creating light akin to what stars emit. The first beam will then be directed into the center of the can, and the two photon sources will collide. What emerges from the can: electrons and positrons. It is "a very clean experiment: pure light goes in, pure matter comes out.

Scientists discover how to turn light into matter after 80-year quest

imagephoton-photoncollider.jpg

Breit and Wheeler suggested that it should be possible to turn light into matter by smashing together only two particles of light (photons), to create an electron and a positron – the simplest method of turning light into matter ever predicted. The calculation was found to be theoretically sound but Breit and Wheeler said that they never expected anybody to physically demonstrate their prediction. It has never been observed in the laboratory and past experiments to test it have required the addition of massive high-energy particles.

This experiment would recreate a process that was important in the first 100 seconds of the universe and that is also seen in gamma ray bursts, which are the biggest explosions in the universe and one of physics' greatest unsolved mysteries.

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#77 2014-05-19 19:56:00

JoshNH4H
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Re: Relativity of light - light at light speed

I don't disagree with any of that.  It sounded to me that you were saying that light has a rest mass, which is impossible (I suppose you could argue that photons are very short lived, very low mass particles moving just shy of the speed of light, but I don't know why anyone would be inclined to do so).

In any case, radiation at 3 K corresponds to 4.6e-6 W/m^2.  This means that a sphere with a diameter of 1 m will have 1.4e-5 W incident on it, with a residency time of 3.3e-9 s.  This means that it will contain 4.8e-14 J, or 9.2e-14 J/m^3.  This is 1.0e-30 kg/m^3.  Multiplied over the approximate volume of the galaxy of about 10^63 kg, this corresponds to 10^33 kg.  Compared to the mass of the galaxy, at around 10^42 kg, this is not enough to account for even a small fraction of the missing mass.

For the mass of light to account for a significant portion of the "dark matter", the galaxy would have to have a mean temperature above 2,000 K. 

All of this, of course, has little to do with a fractally dimensional structure of the universe.


-Josh

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#78 2014-05-21 17:48:31

SpaceNut
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Re: Relativity of light - light at light speed

200px-Light_cone.svg.png

What if in the image, the 0,0 point changes passage of time to space (which is matter and energy) when the speed of light c=0 and at this point it turns into dark matter and dark energy.

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#79 2014-05-21 18:01:31

RobertDyck
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Re: Relativity of light - light at light speed

Ah, light cones. The EPR paper used the light cone argument. The argument was no information could travel faster than light. But of course that isn't the case. And here is one place that relativity disagrees with my idea. Actually, in this case my idea is consistent with quantum mechanics. It explains something that quantum mechanics can describe with math, but doesn't explain why.

Flexible dimension hypothesis states that for a quantum entangled particle pair, the dimension between them just doesn't exist. A pair of photons are 3 dimensional objects in our 4 dimensional space-time universe. The dimension along the line between them just doesn't exist. So from the perspective of the pair of photons, they're sitting on each other. Whatever you do to one, immediately affects the other, because from the particle's perspective there is no distance between them. This is true no matter how much distance in our universe separates them. That can be used for instantaneous communication across significant distance. A pair of electrons are 3 and a little bit dimension objects in our 4 dimensional space-time universe. For them, the dimension between entangled particles again doesn't exist, so again from their perspective they're sitting on each other. No distance, no light cone. If the fraction of a dimension ever rotates to be along the line between them, that would instantly break the entanglement link. Manipulating the electrons too roughly could do that.

Here's another prediction. If a quantum singularity (black hole) were to pass between entangled particles, that would also break the entanglement link. But it might require the quantum singularity itself passing through a corridor the width of a single electron. Passing the event horizon across that line may not be enough.

Last edited by RobertDyck (2014-05-21 18:03:10)

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#80 2014-05-21 18:17:50

SpaceNut
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Re: Relativity of light - light at light speed

Back to mass of a photon, I am thinking that a solar sail is part of how to explain how it could have mass.

energy/speed of light=momentum

which is the product of the mass and velocity of an object. That said does the photon transfer energy only to the sail or does it bounce off or does it change to new at rest mass that the sail now has.

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#81 2014-05-21 19:29:11

RobertDyck
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Re: Relativity of light - light at light speed

I assume that a black sail would gain momentum of a photon. That is, energy of a photon converted to mass, multiplied by speed of light. A reflective sail would reverse direction of photons, so total speed change is twice the speed of light, therefor twice the momentum. That's how it works when a ball bearing strikes a rubber ball. And conservation of energy states it must. Reflection at an angle (tacking) would involve vector math. Know what I mean?

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#82 2014-05-24 00:17:39

SpaceNut
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Re: Relativity of light - light at light speed

Solar radiation pressure from 1.412 kW/m² in early January (147 million km / 91 million miles (.98 AU))  to 1.321 kW/m² in early July (152 million km / 94 million miles (1.1 AU)) for Earth, Venus is 2.5 kW/m2 (Average: 108 million km / 67 million miles (.722 AU)) while mars is 598 W/m2..(Average: 228 million km / 142 million miles (1.52 AU))

The number of photons per square meter is less at a distance from the source which is a sine function of the triangle distance to base spread or the mass of the same number photon at any distance is getting less in mass as the distance increases from the sun.

Last edited by SpaceNut (2014-05-24 20:14:29)

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#83 2014-05-28 20:56:59

SpaceNut
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Re: Relativity of light - light at light speed

Failed dwarf galaxy survives galactic collision thanks to full dark-matter jacket according to a new analysis of data from the National Science Foundation's Robert C. Byrd Green Bank Telescope (GBT).

Astronomers believe that without this protective shell, the high-velocity cloud (HVC) known as the Smith Cloud a halo of dark matter invisible stuff that makes up roughly 80 percent of all the matter in the Universe.

HADES searches for Dark Matter

Although Dark Energy and Dark Matter appear to constitute over 95 percent of the universe, nobody knows of which particles they are made up. Astrophysicists now crossed one potential Dark Matter candidate - the Dark Photon or U boson - off the list in top position.

The interpretation of current astrophysical observations results in the striking mass-energy budget of matter in the universe: 75% Dark Energy and 20% Dark Matter. Only about 5% of the universe consists of "ordinary", baryonic matter.

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#84 2014-06-02 19:44:25

SpaceNut
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Re: Relativity of light - light at light speed

Rush a light wave and you'll break its data

The speed of light in vacuum is often thought to be the ultimate speed limit, something Einstein showed to be an unbreakable law. But two years ago,** members of the research team found a sort of "loophole" in the law when they devised a new way to push part of the leading edge of a pulse of light a few nanoseconds faster than it would travel normally

The team set up a new experiment that "entangled" the photons in two different light beams, which means that quantum information in one beam-such as amplitude-is strongly correlated to information in the other.

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#85 2014-06-02 19:54:37

SpaceNut
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Re: Relativity of light - light at light speed

Since I have spoken of data transfer then the idea of 'Star Trek' teleportation style works on sub-atomic particles

A team of researchers at the Delft University of Technology in the Netherlands recently demonstrated the ability to teleport information in sub-atomic particles between two points about 10 feet apart.

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#86 2015-01-24 19:17:17

SpaceNut
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Re: Relativity of light - light at light speed

Scientists slow down light particles

The speed of light is a limit, not a constant -- that's what researchers in Glasgow, Scotland, say. A group of them just proved that light can be slowed down, permanently.

Scientists already knew light could be slowed temporarily. Photons change speeds as they pass through glass or water, but when they exit the other side and return to a vacuum (like outer space) they speed back up.

In a new experiment at the University of Glasgow, however, scientists were able to permanently manipulate light's speed by passing photons through a device that alters their structure. The device, created in collaboration with researchers at Heriot-Watt University in Edinburgh, is a filter of sorts that the scientists refer to as a mask.

"That mask looks a little bit like a bull's-eye target," researcher Miles Padgett told BBC News. "And that mask patterns the light beam, and we show that it's the patterning of the light beam that slows it down.

"But once that pattern has been imposed -- even now the light is no longer in the mask, it's just propagating in free space -- the speed is still slow," Padgett added.

In other words, the beam of light is reorganized in a way that slows down each individual photon. When tested in a vacuum next to a regular light beam. Photons that had been filtered through mask were milliseconds behind in a sprint to the end of the vacuum racetrack.

Researchers, whose latest work was published this week in the journal Science Express, say the findings prove the speed of light is not an absolute, more like a ceiling.

"It's very impressive work," Robert Boyd, an optical physicist at the University of Rochester who wasn't involved with the study, told Science Magazine. "It's the sort of thing that's so obvious, you wonder why you didn't think of it first."

Did I read that correctly that light which is slowed can speed back up? So where was the energy input to make that happen?

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#87 2015-01-31 20:33:52

SpaceNut
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Re: Relativity of light - light at light speed

Brillouin Scattering Induced Transparency (BSIT), Researchers use sound to slow down, speed up, and block light

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#88 2015-02-10 23:31:00

SpaceNut
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Re: Relativity of light - light at light speed

Dark matter seen in the Milky Way's core

PW-2015-02-10-milky-way.jpg

Scientists first inferred dark matter's existence from the fact that galaxies such as the Milky Way rotate faster than would be expected if they were held together by just the gravitational forces between visible matter such as gas, dust and stars. While it is apparent that the gravitational attraction of invisible dark matter is holding galaxies together.
This result means that there are significant quantities of dark matter well inside the 8 kpc radius of the Milky Way, provided that Newtonian dynamics holds true. This last qualification is crucial, because a minority of astrophysicists argue that the discrepancies between predicted and observed rotation curves are better explained by modifying Newtonian dynamics at large distances, rather than the presence of invisible matter.

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#89 2015-02-24 21:00:28

SpaceNut
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Re: Relativity of light - light at light speed

Could the Sun be trapping asymmetric dark matter?

PW-2015-02-23-dark-matter-sun.jpg

I am going to need to read this a few times to get all of what is said...

Unexplained discrepancies between mathematical models of the Sun and astronomical observations could be resolved by the presence of dark matter in the Sun, according to the latest work from an international team of researchers. The team's model – which looks at dark matter that has a particular, momentum-dependent interaction with normal matter – explains the observed data much better than more conventional dark-matter models. The researchers believe that the particles they postulate could potentially be seen either by direct detectors or in particle accelerators.

In recent years, scientists have reduced their estimates of the proportion of elements heavier than hydrogen and helium in the Sun. These new estimates, based on reinterpretations of spectroscopic data, create a problem. When applied to conventional mathematical models of the solar structure, they create multiple conflicts with the values of various quantities that are measured by looking at periodic changes in size of the Sun caused by acoustic pressure waves. This study of the internal structure of the Sun via acoustic waves is known as helioseismology. To resolve these inconsistencies, researchers are seeking new ways that heat can reach the surface of the Sun from its core. One possibility is that the Sun might contain dark matter that it captures as it passes through the galactic halo. Such matter could carry heat from the core to the cooler outer layers of the Sun.

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#90 2021-06-29 14:41:53

Mars_B4_Moon
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Registered: 2006-03-23
Posts: 9,267

Re: Relativity of light - light at light speed

Seen as there was a lot of Singularity, Exotic Matter and Blackhole talk in this thread


Here's a news item
https://www.npr.org/2021/06/29/10110474 … vitational
Astronomers Find Two Black Holes Gulping City-Sized Neutron Stars

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#91 2021-06-29 20:26:12

SpaceNut
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Re: Relativity of light - light at light speed

Some how we were able to see that the speed of light can be changed...

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#92 2022-04-15 09:17:49

Mars_B4_Moon
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Registered: 2006-03-23
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Re: Relativity of light - light at light speed

'Could The Universe Be Inside A Black Hole?'

https://www.youtube.com/watch?v=jeRgFqbBM5E

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