May 5th, 2006

homuncul

КОСМОЛОГИЯ

NewScientist: Is string theory in trouble? (Dec. 2005)
Talk with Leonard Susskind, the Felix Bloch Professor of Theoretical Physics at Stanford University in California.

- ...we no longer have any good reason to believe that our tiny patch of universe is representative of the whole thing.


NewScientist: Cyclic universe' can explain cosmological constant (May 2006)
Paul Steinhardt (Princeton University) and Neil Turok (Cambridge University) suggest a series of big bangs and "big crunches" could solve the puzzle of our cosmological constant.

"Ever since the 1960s, people assumed that the big bang was the beginning of time, because the laws of physics seem to break down there," says Turok. But the equations of string theory tell a different story, allowing time to exist before the big bang, he says.

"Эксперт" о теории циклической Вселенной

Элементы.ру: Обзор физических публикаций в Nature (Апрель 2006)
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NEUROSCIENCE

'Reset Switch' for Brain Cells Discovered


Duke University Medical Center neurobiologists have discovered how neurons in the brain "reset" when they are overly active. This molecular reset switch works to increase or decrease the sensitivity of brain cells to stimulation by their neighbors. Such "homeostatic plasticity" is critical for the brain to adapt to changes in the environment -- either to avoid having its neurons swamped by increased activity of a neural pathway, or rendered too insensitive to detect triggering impulses from other neurons when neural activity is low. This plasticity is distinct from the more rapid changes in neural circuits laid down early during the formation of memories, said the scientists.

Duke University Medical Center News Release (2003)
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