(±0.2 Billion Years.)

Do chemistry

Thu, 02 May 2013 22:48:45 +1200

Do chemistry

oblivioncontinuum: Time Dilation Time dilation is pretty much the basis for Einstein’s theory of...

Wed, 06 Mar 2013 17:37:45 +1300

Time Dilation

Time dilation is pretty much the basis for Einstein’s theory of special relativity. To explain what it is, it’s important to know what a frame of reference is.

A common analogy used is to imagine someone is on a train bouncing a basketball. When the train is moving, whoever is bouncing the ball will simply see the ball moving up and down. However, to someone who is not on the train, the ball will appear to move a bit like this:

This is an example of two different frames of reference, the one on the train and one off the train both observe different things. Now imagine that train is going really fast, like half of the speed of light, and replace the basketball with a device to measure time.

Since electromagnetic radiation (light) travels at the same speed in a vacuum, the ‘timer’ should measure light in some way. The timer, shown below, has an emitter that emits a photon or beam of light, and a receiver, that detects the light. For simplicity, I’m going to assume that L₀ is very large compared to d₀ so that the light travels directly up and down. The time taken for this process, which we call ∆t is equal to the distance the light travels, divided by the speed of light (c).

∆t₀= 2L₀/c (equation 1)

So while the train is not moving, both observers can agree on what ∆tequals. When the train reaches a constant velocity, half the speed of light, the observer who didn’t get on the train will see train-person’s ‘timer’ do this:

Now the light has to travel much further to reach the receiver (rather than just straight up and down), and therefore the stationary observer sees the person on the having a slower time interval. Focusing on the frame on reference that the stationary observer is in, the time interval ∆tis the same as equation 1, but from the stationary observer’s point of view, the time interval will be different.

If you want to read the math part:

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SCIENCE NEEDS YOUR HELP!

Wed, 27 Feb 2013 08:56:43 +1300

geeklearnstorun:

Help! The Los Angeles Science Fair is being cancelled just three weeks before the event due to insufficient funding.

Over 4,000 students have been working diligently since July to compete in this science fair. They are not able to compete in any other counties and will not be able to compete regionally or nationally this year or next if the LA Science Fair is cancelled. One of my best friends is one of these students. He’s been working towards his culminating project since he was 13 and building microbial fuel cells; he’s now a high school senior and may graduate having never been able to compete with his final project.

We need help right now to make this year’s competition happen. Every dollar helps; you can donate here: http://www.lascifair.org/donorspartners/donate-now/

We’re one of the most competitive science fairs in the country; in cancelling this science fair, we’re cutting hundreds of incredible young scientists clean out of the race.

This is about kids loving science. Please don’t let them down. Please please please donate. We’re currently $70,000 short for this year and, if things don’t look up, there will be no 2013 or 2014 science fair.

http://www.lascifair.org/donorspartners/donate-now/

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physicsandsex: A cation

Tue, 26 Feb 2013 21:55:45 +1300

physicsandsex:

A cation

plant-a-day: Photos courtesy of...

Tue, 26 Feb 2013 21:32:59 +1300

plant-a-day:

Photos courtesy of gardeningwithwilson.

Aristolochia grandiflora or Pelican Flower. It’s a vine and the flowers smell of carrion.

Thought you guys would like to know that I’m not dead and...

Tue, 26 Feb 2013 16:38:41 +1300

Thought you guys would like to know that I’m not dead and that I got a tattoo.

Still alive. Life reached new low. Probably going to avoid tumblr forever. Thank you all. Keep...

Sat, 22 Dec 2012 20:41:58 +1300

Still alive. Life reached new low. Probably going to avoid tumblr forever. Thank you all. Keep science-ing it up.

"I started inventing things, and I couldn’t stop, like beavers, which I know about. People..."

Fri, 16 Nov 2012 20:44:00 +1300

“I started inventing things, and I couldn’t stop, like beavers, which I know about. People think they cut down trees so they can build dams, but in reality it’s because their teeth never stop growing, and if they didn’t constantly file them down by cutting through all of those trees, their teeth would start to grow into their own faces, which would kill them. That’s how my brain was.”

- Oskar Schell, Extremely Loud & Incredibly Close by Jonathan Safran Foer

freshphotons: “Recently one Sunday I spent the day at the...

Fri, 16 Nov 2012 09:52:54 +1300

freshphotons:

“Recently one Sunday I spent the day at the kitchen table playing with oranges, copper wires and galvanized nails. My hope was that I could make this on going project work with a single piece of fruit. I tried cutting it into slices and wedges but that ever present voice in my head reminded me the SIMPLER IS BETTER. It only seemed logical to use the orange’s natural wedges as the cells for the battery. The wedges are held up-right with an armature of small wooden skewers. The LED is nestled with in the bounds of the orange wedges. I’m still amazed this worked…though it did require 14 hours of exposure.” -Caleb Charland

These socks will be our little secret tumblr.

Mon, 12 Nov 2012 11:32:42 +1300

These socks will be our little secret tumblr.

holymoleculesbatman: Calcite, fluorite, Princeton, NJ (midrange...

Sun, 11 Nov 2012 19:18:00 +1300

holymoleculesbatman:

Calcite, fluorite, Princeton, NJ (midrange UV)

miabuterflie: But of course, the nerdiest joke I know: What happens when you cross a mosquito with...

Sun, 11 Nov 2012 12:10:30 +1300

miabuterflie:

But of course, the nerdiest joke I know:

What happens when you cross a mosquito with a mountain climber?

Nothing. You can’t cross a vector with a scalar.

"Every account of a higher power that I’ve seen described, of all religions that I’ve..."

Sat, 10 Nov 2012 12:51:00 +1300

“Every account of a higher power that I’ve seen described, of all religions that I’ve seen, include many statements with regard to the benevolence of that higher power. When I look at the universe and all the ways the universe wants to kill us, I find it hard to reconcile that with statements of beneficence.”

- Neil deGrasse Tyson [source]

prostheticknowledge: Rocking Knit A rocking chair-powered...

Fri, 09 Nov 2012 14:25:07 +1300

prostheticknowledge:

Rocking Knit

A rocking chair-powered knitting machine that can make winter hats, put together for ECAL’s exhibition called “Low Tech Factory” by Damien Ludi and Colin Peillex. Video embedded below:

ECAL Low-Tech Factory/Rocking-Knit from ECAL on Vimeo.

“Rocking-Knit” is a new interpretation of the rocking chair. It offers its user productive moments of relaxation. The to-and-fro movement of this armchair knits hats for the winter and requires no exertion whatsoever.

You can find out more about the exhibition at ECAL here

sciencecenter: A bioluminescent Parapandulus shrimp Beautiful...

Fri, 09 Nov 2012 10:08:29 +1300

sciencecenter:

A bioluminescent Parapandulus shrimp

Beautiful image, right? Oh, by the way, that blue stuff is shrimp puke.

To produce these van Gogh-like swirls, the shrimp vomits up chemicals that react together to produce light. This particular shrimp was photographed in the Bahamas, during an expedition in the Johnson-Sea-Link submersible near the sea floor. The mission? To poke sea creatures and see if they would glow.

prussiahasinvaded: ichthyologist: Net Casting Spider (Deinopis...

Fri, 09 Nov 2012 09:55:40 +1300

prussiahasinvaded:

ichthyologist:

Net Casting Spider (Deinopis sp.)

The net casting spider is named for its strange hunting behavior.

The spider casts a net made of sticky coils of silk and suspends it between its front legs, while dangling above a surface. When prey passes under it, the spider propels itself forward, casting its net over the prey and trapping it in the silk.

El Cucurucho on Flickr

I find this both amazing and terrifying

sciencecenter: Carl Linnaeus and his Autoscopic Double Carl...

Fri, 09 Nov 2012 08:04:01 +1300

sciencecenter:

Carl Linnaeus and his Autoscopic Double

Carl Linnaeus is most famous for being the father of modern taxonomy. But as chronicled in his new book Hallucinations, Dr. Oliver Sacks describes how Linnaeus is notorious for something quite different - he saw himself in double.

Linnaeus suffered from migraine attacks, and according to neurologist Macdonald Critchley, when his headaches came on, he’d hallucinate. A second, phantom Carl Linnaeus would often appear — seen only by the first — and would float about, doing whatever Real Carl was doing. So Linnaeus would be in his garden, checking out a plant or plucking a flower, and he could see, at a respectful distance, the Other Carl stooping and plucking the same way at the same time. Linnaeus didn’t fear his phantom; in fact he got used to it.

As Critchley describes it, the phantom might sit in Linnaeus’ seat at his library desk, and Real Linnaeus, would, presumably, ignore him. One time, Professor Linnaeus was lecturing at his university and decided to run down to his office to fetch a specimen to show the class, and Critchley says, he got to his office, “He opened the door rapidly, intending to enter, but pulled up at once saying, ‘Oh! I’m there already.’ “

Sacks describes this totally-not-made-up condition as something called autoscopy, and though it’s obviously not common, there is quite a bit already known about autoscopic doubles. For example, autoscopic doubles are always mirror images, so one’s right side is transposed onto the left side and vice versa. Sacks also explains how “the double is a purely visual phenomenon, with no identity or intentionality of its own. It has no desires and takes no initiatives; it is passive and neutral.” Autoscopic doubles are also accompanied by unpleasant symptoms like migraines, epilepsy, post-traumatic disorders, and other brain issues. But man, wouldn’t it be fascinating to have a double for just a day or two?

Just something to think about.

Thu, 08 Nov 2012 15:42:37 +1300

check-yo-facts:

nievietie:

Something I thought tumblr peeps might want to know about.

Sir Isaac Newton was gay. The man who discovered gravity and gave it a name was involved with a swiss mathematician, Nicolas Fatio.

Sadly, their relationship ( supposedly) ended badly after 4 years as Fatio began threatening Newton that he would expose his alchemy studies to the public ( keep in mind Newton held himself as a man of science and thought magic would discredit him).

First and foremost, correlation does not prove causation. The mere relationship between two people isn’t grounds for proof of any sexual activity. Newton was as far as anyone can tell non-sexual [source] (something also shared with Tesla). All evidence we can find for Newton’s homosexuality seems largely based off the fact that he didn’t commit to heterosexual relationships and never in fact married [source]. Furthermore Newton was strongly Christian which implies he may never have engaged in any sexual encounter even a heterosexual one.

Any claim that he was homosexual is based purely on conjecture and a romantic interpretation of his letters and not on hard evidence [source].

freshphotons: “The image is the result of fiber tractography...

Thu, 08 Nov 2012 13:46:57 +1300

freshphotons:

“The image is the result of fiber tractography from diffusion-weighted magnetic resonance imaging. It illustrates the white matter of the brain, or in other words, its structural connections. The red smooth surface represents a glioblastoma tumor. We can see the effect of repulsion and infiltration of this mass on the white matter fiber pathways. A distance colormap is used for interpretation. Blue fibers mean that they are located within a safe distance of the tumor whereas red fibers are in a close perimeter to the tumor, and can cause severe post-operation deficits, if resected.” -Cerebral Infiltration, Maxime Chamberland, David Fortin, Maxime Descoteaux, Sherbrooke Connectivity Imaging Lab.

sci-fact: “ I am among those who think that science has great...

Thu, 08 Nov 2012 12:34:38 +1300

sci-fact:

“ I am among those who think that science has great beauty. A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale. ”
_{~ Marie Curie; (Born 145 years ago today, November 7, 1867)}

“All my life through, the new sights of Nature made me rejoice like a child.”
-Pierre Curie