Wood joinery

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This might be the wrong place to ask this question? But you guys on here are pretty resourceful to say the least. We occasionally make a wood joint (not decorative & usually not seen) where we take a 3/4" thick board or piece of plywood. Say 4" wide x however long & at the desired location

From Eternity to Book Club: Chapter Ten | Cosmic Variance

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Welcome to this week’s installment of the From Eternity to Here book club. This is a fun but crucial part of the book: Chapter Ten, “Recurrent Nightmares.”

Excerpt:

Fortunately, we (and Boltzmann) only need a judicious medium-strength version of the anthropic principle. Namely, imagine that the real universe is much bigger (in space, or in time, or both) than the part we directly observe. And imagine further that different parts of this bigger universe exist in very different conditions. Perhaps the density of matter is different, or even something as dramatic as different local laws of physics. We can label each distinct region a “universe,” and the whole collection is the “multiverse.” The different universes within the multiverse may or may not be physically connected; for our present purposes it doesn’t matter. Finally, imagine that some of these different regions are hospitable to the existence of life, and some are not. (That part is inevitably a bit fuzzy, given how little we know about “life” in a wider context.) Then—and this part is pretty much unimpeachable—we will always find ourselves existing in one of the parts of the universe where life is allowed to exist, and not in the other parts. That sounds completely empty, but it’s not. It represents a selection effect that distorts our view of the universe as a whole—we don’t see the entire thing, we only see one of the parts, and that part might not be representative. Boltzmann appeals to exactly this logic.

After the amusing diversions of the last chapter, here we resume again the main thread of argument. In Chapter Eight we talked a bit about the “reversibility objection” of Lohschmidt to Boltzmann’s attempts to derive the Second Law from kinetic theory in the 1870’s; now we pick up the historical thread in the 1890’s, when a similar controversy broke out over Zermelo’s “recurrence objection.” The underlying ideas are similar, but people have become a bit more sophisticated over the ensuing 20 years, and the arguments have become a bit more pointed. More importantly, they are still haunting us today.

One of the fun things about this chapter is the extent to which it is driven by direct quotations from great thinkers — Boltzmann, of course, but also Poincare, Nietzsche, Lucretius, Eddington, Feynman. That’s because the arguments they were making seem perfectly relevant to our present concerns, which isn’t always the case. Boltzmann tried very hard to defend his derivation of the Second Law, but by now it had sunk in that some additional ingredient was going to be needed — here we’re calling it the Past Hypothesis, but certainly you need something. He was driven to float the idea that the universe we see around us (which, to him, would have been our galaxy) was not representative of the wider whole, but was simply a local fluctuation away from equilibrium. It’s very educational to learn that ideas like “the multiverse” and “the anthropic principle” aren’t recent inventions of a new generation of postmodern physicists, but in fact have been part of respectable scientific discourse for over a century.

Boltzmann's multiverse

It’s in this chapter that we get to bring up the haunting idea of Boltzmann Brains — observers that fluctuate randomly out of thermal equilibrium, rather than arising naturally in the course of a gradual increase of entropy over billions of years. I tried my best to explain how such monstrosities would be the correct prediction of a model of an eternal universe with thermal fluctuations, but certainly are not observers like ourselves, which lets us conclude that that’s not the kind of world we live in. Hopefully the arguments made sense. One question people often ask is “how do we know we’re not Boltzmann Brains?” The realistic answer is that we can never prove that we’re not; but there is no reliable chain of argument that could ever convince us that we are, so the only sensible way to act is as if we are not. That’s the kind of radical foundational uncertainty that has been with us since Descartes, but most of us manage to get through the day without being overwhelmed by existential anxiety.


Wireless Gravestone Tech Will Broadcast Your Awesomeness to Posterity | Discoblog

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RosettaStoneFor those people seeking some long-term postmortem respect, you could always go the route of the Royal Tenenbaum epitaph and have your hyperbolic greatness engraved upon a headstone. But we all know weather eventually gets the better of those words, and besides: Why settle for one measly sentence when you could speak directly to your descendants from beyond the grave?

The Objecs company has the answer: RosettaStone “technology enhanced memorial products,” which, preloaded with your autobiographical information, will attach to your grave. From Discovery News:

When your great-great-great granddaughter stops by sometime in the next century and wants to know who you were, she’ll touch her NFC-RFID enabled cellphone (or whatever device we’re using by then) to one of those symbols on the granite iPod-looking device on your headstone and she’ll get your note.

NFC stands for “near-field communication” which is a subset of RFID – “radio frequency identification.” You’re probably using this technology already. RFID is what allows you to pay a toll while driving 30 mph by way of the little box stuck to your rearview mirror.

As the above passage notes, the practicality of RosettaStone depends on it working with the cellphone technology of the future that will probably be directly implanted in your head, or perhaps that someone will care enough after you’re gone to drop by the cemetery and upgrade your headstone.

Still, it could work. So please, no stupid text abbreviations in your autobiography. This is for posterity.

Related Content:
Discoblog: “Gravestone Project” Takes Citizen Science to the Cemetery
80beats: Egypt Finds Tombs of Pyramid Builders, And More Evidence They Were Free Men

Image: Objecs LLC


Keep the Medical, Well, Medical

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Dr. Steven Murphy writes an excellent post about his stance in medical genomics and why he does not support today’s “Direct to Consumer” genomic industry. Highlights:

Medicinally used genetic tests, whether DTCG or not, should be represented and treated as Medical Tests…

Medical Genetic tests should be regulated according to the laws of each state/country…

Simply stating your tests are “nonmedical” does not make them “nonmedical” especially if they have a long history of being used medically…

I know many people who read this website do not like Dr. Steven Murphy. But that is a damn fine argument, and the truth is, Steve believes in personalized medicine so much that he built an entire medical practice to do it. Sick people come in, and healthy people come out. Everyday. So, you’re a “personalized medicine” advocate? What did you do? Link from your blog? Raise awareness? How many patients got medical help from you? Zero? “but… um, I helped contribute awareness and advocate….” Yah… nothing. That’s what I thought.

I support Steve. You may not like his online persona. You may not like the personality stereotype of all doctors. But remember: nobody liked the “personality type” of “electrical engineers” in the 1970’s, either.

Aside: and all this hate toward Myriad: listen, you may not like Myriad. But they have been healing patients for decades before you even knew what DNA was. Have some respect. Oh, so you don’t like “gene patents”? Me neither. But, take it to court… and I sure as hell hope you have better arguments than “it’s like looking in the mirror” and “if something new is created, then you can’t make diagnostics.” Cut the “oh some evil company wanted to bill me a couple hundred dollars for a medical test boo hoo” trial-by-mob bullshit. Yah. My business is medical operations. You want a boo hoo story? I have real boo hoo stories for you. Run a decent case and keep the half-assed sob stories to yourself.

Artwork of DEATH! | Bad Astronomy

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A few months ago, I wrote about an art exhibit in NYC based on my book Death from the Skies! Brian George, one of the artists who put this exhibit together, just posted a very cool blog entry about it too.

He posted some great picture on Picasa, which you can see in the slideshow below or on Picasa directly.

I am totally blown away by the sculpture Solar Flares and CMEs. In the book, I describe how the tangling of the Sun’s magnetic field lines is like a bag full of springs under tension. How I pictured that in my head is almost exactly duplicated by that piece.

I could not get to NYC for the exhibit, but I really wish I had. The artwork is amazing, almost as amazing as the feeling I get thinking that a book I wrote for my own nefarious purposes actually inspired a group of artists to create such wonderful and astonishing pieces. My thanks to all of them for swelling my head just a little bit more.


Banana Compound May Lead to Treatment to Prevent Spread of HIV – eMaxHealth

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TheMedGuru
Banana Compound May Lead to Treatment to Prevent Spread of HIV
eMaxHealth
University of Michigan Medical School scientists may have found an inhibitor of HIV derived from bananas that can help to prevent sexual transmission of the ...
Ingredient in Bananas May Prevent HIV TransmissiondBTechno
Banana beats anti-HIV drugsIndependent
Bananas enlisted to help stop spread of HIVMontreal Gazette
Marie Claire.co.uk -Times of India -Mother Nature Network
all 78 news articles »

NASA Finds Shrimp Where No Advanced Life Should Be: 600 Feet Beneath Antarctic Ice | 80beats

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There’s a lot more going on beneath those huge sheets of Antarctic ice than you might think. NASA researchers say they uncovered a major surprise in December: The team drilled an eight-inch hole and stuck a video camera 600 feet down, hoping to observe the underbelly of the thick ice sheet. To their amazement, a curious critter swam into view and clung to the video camera’s cable [Washington Post]. The three-inch crustacean in their video (and pictured in the image here) is a Lyssianasid amphipod, a relative of a shrimp. The team also retrieved what they believe to be a tentacle from a jellyfish.

“We were operating on the presumption that nothing’s there,” said NASA ice scientist Robert Bindschadler, who will be presenting the initial findings and a video at an American Geophysical Union meeting Wednesday. “It was a shrimp you’d enjoy having on your plate” [AP]. Indeed, researchers previously believed that nothing more complex than microbes could live in such a hostile place, beneath an ice sheet in total darkness. While complex organisms have shown up before in retreating glaciers, this seems to be the first time any have been found 600 feet down below an intact sheet of ice.

The sheer unlikeliness of the find (what would these creatures eat, after all?) cast doubt in the minds of some scientists that this is the organisms’ true habitat. The site is connected to the open sea, says Cynan Ellis-Evans of the British Antarctic Survey. But given the distance to that open sea—12 miles–study coauthor Stacy Kim says it’s highly unlikely such small creatures made such a journey under an ice sheet. In addition, the hole NASA drilled measured only eight inches across. That means it’s unlikely that that two critters swam from great distances and were captured randomly in that small of an area, she said [AP].

If crustaceans really can tough it out buried beneath the ice, perhaps complex organisms can live in more places than we give them credit for. Astrobiology enthusiasts are probably already thinking of the ice-covered moons in our solar system, like the Jovian moon Europa and the Saturnian moon Enceladus, and wondering whether extraterrestrial critters could be lurking beneath those frozen surfaces. First, though, there’s a lot left to sort out about this intriguing puzzle.

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Related Content:
80beats: An Iceberg the Size of Luxembourg Breaks Free from Antarctica
80beats: Is the Once-Stable Part of Antarctica Starting to Melt?
80beats: Fossils of Shrimp-Like Creatures Point to Warmer Antarctica in the Distant Past
80beats: Floods Beneath Antarctica’s Ice Sheet Create a Glacial Slip-and-Slide

Image: NASA