22 July posts:

Astronomy: a heavy main sequence star has been discovered:

A newfound star has shattered the record as the most massive stellar monster ever seen, astronomers announced today.

Weighing in at a whopping 265 times the mass of our sun, the behemoth may have actually slimmed down since birth, when it likely tipped the scales at 320 times the sun’s mass.

The discovery could rewrite the laws of stellar physics, since it’s long been thought that stars beyond a certain mass would be too unstable to survive.

“We are really taken aback, because up until now the astronomical community at large has assumed that the upper size limit for stars would be around 150″ times the mass of the sun, said study co-author Richard Parker, an astronomer at the University of Sheffield in the U.K.

“This giant could really revolutionize the way we think about how stars form and die in clusters and galaxies.”

Parker’s team found the stellar monster in images taken with the European Southern Observatory’s Very Large Telescope in Chile. The star is tucked inside a dense cluster of other hot, young, massive stars in one of the Milky Way’s satellite galaxies, the Large Magellanic Cloud.

Dubbed R136a1, the record-breaking star is so massive that it burns its hydrogen fuel at an unprecedented rate—fast enough that the star is considered middle-aged at about a million years old. By contrast, our sun is about five billion years old and still has another five billion years to go.

“Because there are so very few places where there is enough gas that can collect and form such massive stars, we may very well be seeing the limit of how large a star can get,” Parker added.

Time travel There is a way to mathematically model time travel in a way that only certain kinds of time travel could occur (e. g., you couldn’t go back in time and kill your parents before they conceived you; this is taking quantum “entanglement” into account:

he model of time travel proposed by Seth Lloyd, et al., in a recent paper at arXiv.org arises from their investigation of the quantum mechanics of closed timelike curves (CTCs) and search for a theory of gravity. In simple terms, a CTC is a path of spacetime that returns to its starting point. The existence of CTCs is allowed by Einstein’s general relativity, although it was Gödel who first discovered them. As with other implications of his theories, Einstein was a bit disturbed by CTCs.

In the new paper, the scientists explore a particular version of CTCs based on combining quantum teleportation with post-selection, resulting in a theory of post-selected CTCs (P-CTCs). In quantum teleportation, quantum states are entangled so that one state can be transmitted to the other in a different location. The scientists then applied the concept of post-selection, which is the ability to make a computation automatically accept only certain results and disregard others. In this way, post-selection could ensure that only a certain type of state can be teleported. The states that “qualify” to be teleported are those that have been post-selected to be self-consistent prior to being teleported. Only after it has been identified and approved can the state be teleported, so that, in effect, the state is traveling back in time. Under these conditions, time travel could only occur in a self-consistent, non-paradoxical way.

“The formalism of P-CTCs shows that such quantum time travel can be thought of as a kind of quantum tunneling backwards in time, which can take place even in the absence of a classical path from future to past,” the researchers write in their paper. “Because the theory of P-CTCs relies on post-selection, it provides self-consistent resolutions to such paradoxes: anything that happens in a P-CTC can also happen in conventional quantum mechanics with some probability.”

Or put another way, Superman couldn’t really save Lois Lane by traveling backwards in time.

News of the strange: is it rape if you lie to a woman who, upon believing your lie, voluntarily sleeps with you? In some countries, it is:

A Palestinian man has been convicted of rape after having consensual sex with a woman who had believed him to be a fellow Jew.

Sabbar Kashur, 30, was sentenced to 18 months in prison on Monday after the court ruled that he was guilty of rape by deception. According to the complaint filed by the woman with the Jerusalem district court, the two met in downtown Jerusalem in September 2008 where Kashur, an Arab from East Jerusalem, introduced himself as a Jewish bachelor seeking a serious relationship. The two then had consensual sex in a nearby building before Kashur left.

When she later found out that he was not Jewish but an Arab, she filed a criminal complaint for rape and indecent assault.

Although Kashur was initially charged with rape and indecent assault, this was changed to a charge of rape by deception as part of a plea bargain arrangement.

Handing down the verdict, Tzvi Segal, one of three judges on the case, acknowledged that sex had been consensual but said that although not “a classical rape by force,” the woman would not have consented if she had not believed Kashur was Jewish.

The sex therefore was obtained under false pretences, the judges said. “If she hadn’t thought the accused was a Jewish bachelor interested in a serious romantic relationship, she would not have cooperated,” they added.

(hat tip: The Edge of the American West)

Ok, here is my question: what about the other way? Example: what if a man has sex with a woman who claims to be Jewish but then really isn’t?

(note: this is a different case than having sex with someone who knowingly has a disease but says that they don’t)

Economy
Robert Reich: we aren’t in a double dip recession yet but rather a 1.5 dip…for now. But will we act?

Political Humor: Tea Party Medical Care (via: Millard Fillmore’s Bathtub, who talks about getting disinvited from a Tea Party gathering as he pointed out that the census is mandated by the Constitution; for example it is used to apportion Representatives in the House.)

Back to the cartoon:

These people (the tea party types) are ignorant in the extreme:

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