De Sitter relativity and Lorentz contraction

In summary, the de Sitter relativity paper discusses how conformal transformations will naturally be incorporated into the kinematics of spacetime, and this will cause the conformal current to appear as part of the Noether conserved current.
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oldman
633
5
De Sitter relativity and Lorentz contraction

I need help in understanding the elements of a paper that I think could turn out to be quite important, namely http://arxiv.org/abs/0711.2274 de Sitter Relativity: a New Road to Quantum Gravity
R. Aldrovandi, J. G. Pereira)

Inter aliathey say that:

in de Sitter relativity “... conformal transformations will naturally be incorporated in the kinematics of spacetime, and the corresponding conformal current will appear as part of the Noether conserved current [7].” This is because “ ... a cosmological term naturally introduces the conformal generators in the definition of spacetime transitivity.”

I understand (probably wrongly) that the main feature of conformal transformations is that they are shape-preserving on a small enough scale. If this is so, I have a question:

Lorentz transformations are not shape-preserving; the Lorentz contaction is uniaxial, as in the explanation of the null-result of the Michelson-Morley experiment.

Are the conformal transformations of de Sitter SR bolt-on additions that leave Lorentz contraction intact, while providing dilation via a non-zero cosmological constant?

And also, what exactly is the "proper conformal current" they talk of? Is it a sort of extra momentum-energy flux?
 
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Off topic but gruesomely notable

J. G. Pereira was one of the victims in the second Turkish Plagiariasm Ring scandal at the archive (the first was centered at METU, the second at COMU); see http://arstechnica.com/articles/culture/plagiarism-and-falsified-data-slip-into-the-scientific-literature.ars and http://arxiv.org/new/withdrawals.aug.07.html.
 
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Thanks, Chris Hillman, and Fredrik, for your kind replies. I wasn't aware of the plagiarism scandal emanating from Turkey --- it must be so easy to patch together articles by cutting and pasting. I'm not surprised that some folk have tried it. And thanks for the pointer to Marcus' thread about this paper, Fredrik. I'm as intrigued by it as he seems to be, and had hoped that a second thread about it would stimulate more discussion.

The Aldrovandi and Pereira paper could just be the start of a new perspective with the potential to rival the impact that Garrett Lisi has had, if their work makes real sense. But the fact that these authors are not alternative-lifestyle Nord Americano surfing-skiing dudes may at first blunt their impact!
 

1. What is De Sitter relativity?

De Sitter relativity is a model of the universe proposed by Dutch mathematician Willem de Sitter in the early 20th century. It describes a universe with a positive cosmological constant, meaning that the expansion of the universe is accelerating. This model is based on Einstein's theory of general relativity and has implications for the structure and evolution of the universe.

2. How does De Sitter relativity differ from other models of the universe?

De Sitter relativity differs from other models, such as the Friedmann-Lemaître-Robertson-Walker (FLRW) model, in that it includes a positive cosmological constant. This constant represents the energy density of the vacuum and has the effect of causing the expansion of the universe to accelerate over time.

3. What is Lorentz contraction?

Lorentz contraction, also known as length contraction, is a phenomenon predicted by special relativity. It states that objects moving at high speeds will appear shorter in the direction of motion when measured by an observer at rest. This effect becomes more pronounced as the speed of the object approaches the speed of light.

4. How does De Sitter relativity affect Lorentz contraction?

De Sitter relativity has a significant impact on Lorentz contraction because the model predicts an accelerating expansion of the universe. As the universe expands, objects within it are pushed farther apart, resulting in a greater observed contraction in their lengths. This phenomenon has been confirmed by observations of distant galaxies and the cosmic microwave background radiation.

5. How does De Sitter relativity fit into our current understanding of the universe?

De Sitter relativity is an important model in our current understanding of the universe. It helps explain the observed acceleration of the expansion of the universe, which was first discovered in the late 1990s. This model also has implications for the ultimate fate of the universe, as it suggests that the expansion will continue to accelerate indefinitely, leading to a "Big Rip" scenario in which all matter will eventually be torn apart.

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