Time travel isn’t possible

Paul Raven @ 25-07-2011

Better shelve that plan for a timehopping cultural tour of Renaissance Venice; physicists from the University of Hong Kong are convinced they’ve shown time travel to be impossible.

The possibility of time travel was raised 10 years ago when scientists discovered superluminal – or faster-than-light – propagation of optical pulses in some specific medium, the team said. It was later found to be a visual effect, but researchers thought it might still be possible for a single photon to exceed light speed. Du, however, believed Einstein was right and determined to end the debate by measuring the ultimate speed of a single photon, which had not been done before.

“The study, which showed that single photons also obey the speed limit c, confirms Einstein’s causality; that is, an effect cannot occur before its cause,” the university said.

I’ll give it a maximum of two years before someone has a counter-theory that makes it possible once again…


Not actually “mental time travel” at all, is it?

Paul Raven @ 19-07-2011

But it makes for an attention-grabbing skiffy-tastic headline, AMIRITEZ? The actual story here is rather less OMFG: University of Pennsylvania have obtained the first neurobiological evidence in support of the theory of episodic memory.

“Theories of episodic memory suggest that when I remember an event, I retrieve its earlier context and make it part of my present context,” Kahana said.  “When I remember my grandmother, for example, I pull back all sorts of associations of a different time and place in my life; I’m also remembering living in Detroit and her Hungarian cooking. It’s like mental time travel. I jump back in time to the past, but I’m still grounded in the present.”

Jumping back in time to perceptions of the past while still grounded in the present? Strikes me that rewatching old home movies is at least as good a metaphor as time travel, but I’ll grant you that a lot less people would have reported it if it were pitched that way.

Neuroscience is still a fairly new scientific frontier, and while the last decade has seen the arrival of amazing new tools (and enhancements of existing ones), I believe it’s fair to say that these methods are still pretty crude, and the interpretations of results somewhat speculative. But even so, it’s interesting to see these early phases of our attempts to measure something as inherently intangible as the mind:

The memory experiment consisted of patients memorizing lists of 15 unrelated words. After seeing a list of the words in sequence, the subjects were distracted by doing simple arithmetic problems. They were then asked to recall as many words as they could in any order. Their implanted electrodes measured their brain activity at each step, and each subject read and recalled dozens of lists to ensure reliable data.

“By examining the patterns of brain activity recorded from the implanted electrodes,” Manning said, “we can measure when the brain’s activity is similar to a previously recorded pattern. When a patient recalls a word, their brain activity is similar to when they studied the same word.   In addition, the patterns at recall contained traces of other words that were studied prior to the recalled word.”

“What seems to be happening is that when patients recall a word, they bring back not only the thoughts associated with the word itself but also remnants of thoughts associated with other words they studied nearby in time,” he said.

The findings provide a brain-based explanation of a memory phenomenon that people experience every day.

“This is why two friends you met at different points in your life can become linked in your memory,” Kahana said. “Along your autobiographical timeline, contextual associations will exist at every time scale, from experiences that take place over the course of years to experiences that take place over the course of minutes, like studying words on a list.”


Our cancerous common ancestor?

Paul Raven @ 18-03-2011

Peter Watts, still recovering from a close brush with mortality in the form of a flesh-eating virus (pictures NSFL – Not Safe For Lunch), blogs an interesting new scientific paper that suggests that we are all cancer. Take it away, Mister Watts:

I don’t mean this proximally. I mean it in the sense that all birds are dinosaurs — because according to Davies & Lineweaver, cancer (more precisely, “tumor-like neoplasms”) is the common ancestor of all animal life. Every malignant lump on your breast, every metastatic colony proliferating through your marrow, is just a rebooted revisitation of your grandmother a million times removed.

The basic idea’s petty straightforward. Natural selection reaches into every corner of the biosphere, you see; and a billion years ago that meant every cell for itself because unicellular life was the only game in town. A mere six hundred million years back, though, all that had changed. Metazoans were everywhere — cells grouped into colonies with specialized subsystems called tissues and organs —and somehow, within those colonies, the whole beat-the-competition thing had fallen out of favor. Cells worked together, now; hell, red blood cells even gave up their nuclei for the good of the organism, which really puts the kibosh on any future solo career. I think it had something to do with inclusive fitness.

In between, presumably, there was something halfway between Cuba and the US, some intermediate form between everyone for themselves and everyone for the state. Some kind of loose affiliation of cells which valued their individual freedom, but were not above at least some level of cooperation. Modern-day sponges might be a pretty good example: some cellular specialization, a bit of the ol’ helping hand between cells, but nothing so altruistic as an actual tissue. Call it “Metazoa 1.0″. Davies and Lineweaver do.

According to D&L, that old 1.0 operating system is still sleeping down there in our genetic code; it’s just been turned off by the more recent regulatory genes of Metazoa 2.0. It hasn’t been eradicated outright, because a lot of those ancient genes are still useful (“…the genes responsible for the cellular cooperation necessary for multicellularity are also the genes that malfunction in cancer cells.”) It’s just been — tamed, is as good a word as any. Tamed, and deactivated.

Except when something happens to one of those bits of regulatory code that keep it comatose. When some base pair flips this way instead of that, Metazoa 1.0 wakes up, its ancestral toolkit intact, ready to party like it’s One Billion Years B.P.

Watts, trained scientists that he is, is at pains to point out that Davies & Lineweaver are merely looking at old data with a new interpretation, and that they’ve put forward a theory rather than a statement of fact… and yeah, I know most of you who read here already know the difference, but this is the internet, after all. But…

… the great thing about being a science fiction writer is that I don’t really have to wait if I don’t want to. Here is an idea, peer-reviewed and legitimately published, thrown into discourse: We are all descended from Cancer. We are borne of the Holy Tumor. Isn’t that a thought. Doesn’t that get your mind going: to the imagination of ancient habitats, somewhere on this planet or within it. To isolated refugia, cut off from the rest of the world when stromatolites were still young, where 2.0 never happened and the cancerous Metazoan prototype was free to chart its own evolutionary course through a billion years.

I find these sorts of insights into the genesis of story ideas fascinating (as I do the science at the root of them). Though I’m kinda surprised that a guy who was nearly killed off by some incredibly virulent and weird disease a few weeks back (on the tail of having narrowly avoided becoming an anomalous Canadian blip in the 2010 immigration law incarceration statistics of the United States) needs to read biology papers to find potentially horrifying things to write about…


Climate propaganda not profitable

Paul Raven @ 01-03-2011

Ars Technica takes on a climate change denial shibboleth which I’ve always felt was more than adequately dealt with by Occam’s Razor. You know, the one that goes “of course the climate scientists are going to say things are getting worse; how else are they going to ride the government-money gravy train?” Perhaps I’m just lucky to have known enough scientists to make me aware of the fact that climate science – or indeed any science career – isn’t a route to fame, fortune and power (you’d be better off looking in the corridor labelled “politics” for those fringe benefits, AMIRITEZ?), but for everyone else, here’s the skinny:

Since it doesn’t have a lot of commercial appeal, most of the people working in the area, and the vast majority of those publishing the scientific literature, work in academic departments or at government agencies. Penn State, home of noted climatologists Richard Alley and Michael Mann, has a strong geosciences department and, conveniently, makes the department’s salary information available. It’s easy to check, and find that the average tenured professor earned about $120,000 last year, and a new hire a bit less than $70,000.

That’s a pretty healthy salary by many standards, but it’s hardly a racket. Penn State appears to be on the low end of similar institutions, and is outdone by two other institutions in its own state (based on this report). But, more significantly for the question at hand, we can see that Earth Sciences faculty aren’t paid especially well. Sure, they do much better than the Arts faculty, but they’re somewhere in the middle of the pack, and get stomped on by professors in the Business and IT departments.

This is all, of course, ignoring what someone who can do the sort of data analysis or modeling of complex systems that climatologists perform might make if they went to Wall Street.

“Ah, but what about the grant money, huh?”

Funding has gone up a bit over the last couple of years, and some stimulus money went into related programs. But, in general, the trend has been a downward one for 15 years; it’s not an area you’d want to go into if you were looking for a rich source of grant money. If you were, you would target medical research, for which the NIH had a $31 billion budget plus another $10 billion in stimulus money.

There’s more details there for them as wants ’em. Of course, if you’re already convinced that climate science is a liberal plot to make oil barons feel bad, you’ll probably not struggle to conclude that someone slipped Ars an envelope full of grubby grant dollars for their part in propping up the conspiracy… in which case I can only hope that believing so makes it easier for you to sleep at night, because that’s about the greatest utility that such a belief could possibly have.

Speaking of propaganda, here’s a site all about analysing and understanding the messages with which we are bombarded by governments, corporations and special interest groups [via BoingBoing]. Watch for the fnords, folks.


Path dependency is a cultural function, not vice versa

Paul Raven @ 07-02-2011

Via Ken MacLeod, a rebuttal of Neal Stephenson’s theory of path dependency (as mentioned last week):

… the obvious question is why a popular and widely read author [got] his story so wrong, and why so many people believe it now. The answer, of course, is that America, and the developed world, are locked in a path dependent and locked in culture. The reason people believe a randomocity theory of rockets, is because much of our lives are based on relatively random decisions and lock in. So we project backwards. But Adolf Hilter, WSC, FDR, Stalin, were not creatures of the same moment. They had the reverse problem: namely, no one knew what the best technologies were, or the best social structures, to handle a massively disruptive moment.

In otherwords Stephanson is wrong on virtually every point, on every interpretation, but is right about his audience. Allowing them to see the past as making the same mistakes they make in their cubes every day, is an easy way to enormous instant popularity. It’s also a good example of why we are in the mess we are in: people like Stephanson writing for other people like Stephanson about how the weeds are thick and the weeds are somehow aligned against us. No, we are meeting the enemy, and he is us. It isn’t Hitler that is keeping the Ares alive, nor Stalin that is making us build vast banking frauds to prop up demand for suburban homes that aren’t really wanted, nor Truman and Eisenhower who are stopping us from researching fast nuclear power plants. They are de-yad. It must be us.

There’s a second part to come, presumably to explain Stirling Newberry’s antithesis. I’ll be looking out for it…


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