apparent motion

 

from the comments on the facebook post, some people couldn’t see the apparent motion in this figure and some people could start and stop the apparent motion.  once i read that, i learned that i could stop the motion, too, but then it got harder to start it back up… what’s YOUR experience?  anyone know why i checked “math” as one of the categories?

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mri of pineapple

this speeded-up mri of a pineapple was imaged at boston university medical school and a few of the images were published on mashable.com. i particularly like the tomato.gif. mashable has a link to another website that had more images~very rich! but i had too many tabs/windows open and i crashed the browser … maybe another time

 

i first saw this .gif on google+ where someone commented that this is exactly what .gifs were invented for… i’m glad the comment was not regarding the utility of mris!

fun brain teaser

i have to take some issue with the definition of “genius” given in the facebook presentation of this graphic: the caption predicted 85% of respondents would get the answer wrong and only the “genius” 15% would get it correct. the international “high-iq” society (mensa) admits people in the top 2% of iq and i’m not by any means convinced that being in mensa= genius! and my unscientific survey of the over 200,000 responses on facebook did not look as if even 15% had the answer correct… interestingly, the correct answerers simply wrote the number without elaboration; incorrect answerers explained and explained how they derived their mistakes and often insulted folks who had different results ;)

i don’t often get comments on this blog: do you dare???

warp drive

 

A Real Star Trek:

As some of you may have heard, scientists as NASA’s Johnson Space Center are working on warp technology (did your little Trekkie heart just skip a beat?).

In 1994, physicist Miguel Alcubierre proposed a new kind of technology that would allow us to travel 10 times faster than the speed of light, without actually breaking the speed of light. Sound confusing? Well, the Alcubierre drive does not actually propel the ship to speeds exceeding light; instead, it uses the deformation of spacetime permitted by General Relativity to warp the universe around the vessel. Essentially, when the drive is activated the spacetime behind expands, while in the font it contracts. In this respect, the path taken becomes a time-like free-fall. The ship hums along in a little bubble of space, and neither the passengers nor the vessel encounter inertial effects.

This form of travel would make space flight significantly faster. For example, a trip to the nearest star (Proxima Centauri), which rests some four light years from Earth, would ordinarily take over 17,000 years. However, with the Alcubierre drive, it would take a little under five months. For those of us who have a mental breakdown on 10 hour plane flights, 5 months might still seem like quite a bit of travel time. But when we are talking about the vast cosmic distances between Earth and Proxima Centauri, a 5 month trip would be an achievement of monumental proportions (keep in mind, it took Curiosity 8 months just to reach Mars).

Most notably, this method of travel does not involve time dilation. Ordinarily, time slows down as you come closer to the speed of light. So a person traveling really fast might only age 5 months, while the rest of the universe ages 5 million years. But this doesn’t happen with the Alcubierre drive. Since time is also warped, it passes the same for both the traveler and those left behind on Earth.

Scientists at NASA have created a miniature version of the warp drive in their labs, and are attempting to create small warps in space and time. This may be the beginning of real-life warp drive.

…of course, there are some problems we’ll need to overcome first.

The first problem is that this Drive requires prohibitive amounts of energy (a ball of antimatter the size of Jupiter, to be exact). However, scientists reworked Alcubierre’s equations and concluded that, by oscillating the warp bubble and altering the shape of the vessel, the amount of energy needed to create a warp bubble is reduced to a mere 500 kilograms, which is about the size of the Voyager spacecraft (NASA’s Voyager spacecraft…not Captain Janeway’s).

Another problem is that antimatter is horribly dangerous (terribly, horribly dangerous). Interact with a small amount of this energy in the wrong way, you’ll get a blast larger than the energy released during the bombing of Hiroshima. Unfortunately, the 500 kilograms needed for the new ship’s design still requires energy equivalent to 1.5 million Hiroshimas (which is more than enough to destroy civilization and wipe most life off the face of the Earth).

And the last problem: any people or objects at the destination point will be gamma ray and high energy particle blasted into oblivion (we’re talking about the complete and utter annihilation of whole star systems…yeah, just a minor hang-up).

There are a plethora of high-energy particles flying throughout the cosmic void, and research indicates that some of these particles would get swept up in the craft’s warp field (bubble of space) and remain trapped. When the ship reenters normal space, the particles would be released. And relativity indicates that there is no upper limit to the amount of energy an Alcubierre drive could pick up. So travelers on their way to Proxima Centauri could annihilate the system upon their arrival. Even worse, re-positioning the vessel won’t help, as this death ray might be projected in all directions.

However, don’t be too upset. Scientists are still crunching the numbers to see if this technology is really as dangerous as feared. And even if it is super dangerous, it doesn’t mean that we can’t use it to seek out new life and new civilizations…it just means that we might accidentally destroy said new life and new civilizations when we get there.

~Jolene

Another FQtQ article on warp drive:
http://tinyurl.com/byuvrmp

Sources and Further Research:

NASA Says that Warp Drive is Plausible:
http://www.extremetech.com/extreme/136408-nasa-working-on-faster-than-light-travel-says-warp-drives-are-plausible

Warp Drive, on the Matter of Matter:
http://arxiv.org/pdf/1202.5708v1.pdf

Image Source:
http://www.tumblr.com/tagged/warp%20drive?before=18

 

—-

total copy/paste steal from quarks to quasars ~pzykr…

commentary on the facebook, et al, posts below

(see  “TrollMath: Pi”  link below…)

  • pzykr

    nice fractal but no one has succeeded in squaring a circle!

    remember: the very existence of a fractal is based on an impossible premise: that one can write with an infinitely small pencil…

    also there is no limit that the equation that describes the perimeter of the fractal approaches: the equation is p=4, ad infinitum. the box around the circle (the fractal) never can approach the circle itself.

    further comments from the facebook share…

    Arthur Frohlich the reason it doesn’t work is because as the fractal gets infinitely close to the close it becomes a squiggly line going around the edge of the circle instead of the solid line that the circle is made of. the extra distance is stored in the squiggles. great fractal though.
    3 hours ago · Unlike · 1

  • Arthur Frohlich also I’m pretty sure that if you continue that fractal it come out as an octagon or diamond not a circle.
    3 hours ago · Like
  • Jerry Hill that “extra distance” that is “stored in the squiggles” and is unvarying means that the fractal never can get “infinitely close[r] to the [circle]…”
    about an hour ago · Like
  • Jerry Hill that’s what i meant with the comment about no limit that the equation approaches
    about an hour ago · Like
  • Jerry Hill ‎”infinitely close” can never exist because that would involve an undefined operation–that’s why limits exist…
    53 minutes ago · Like
  • Jerry Hill all that said, kudos, @Arthur Frohlich for the phrase “stored in the squiggles.” Nicely said :)
    46 minutes ago · Like
  • Nico Rojas i understand now
    34 minutes ago · Unlike · 1
  • Abdul Ansari  plus, the areas of the two were never equal?

    February 5 at 1:40pm · Like
  • Arthur Frohlich

    Thank you. When I say that the fractal gets infinitely close to the circle I mean that as you continue to contort the square’s perimeter to match that of the circle you eventually have an infinite number of squiggles that are infinitesimal in height, which gives you something that looks very much like a circle.
    Abdul: The areas become extremely close although they will never actually equal. this is because you have to remember that those squiggles contain a small area. it’s similar to 2^(-x) in that it will never actually reach zero although it gets very close.
    Also, you can’t remove the corners as squares because if you remove squares from a right angle you will definitely not get a curve. you would have to be removing rectangles of changing dimensions to get a curve.
    Also, I should be doing a lab report
    February 5 at 10:31pm · Unlike · 1
  • Jerry Hill ah–in your explanation “approaches” would seem to be used in the context that the ~shape~ approaches that of a circle more and more closely: you weren’t saying that the length of the perimeter was changing… good point–i now take your meaning.
    thanks for elaborating

    February 5 at 11:51pm · Like
  • Jerry Hill  and good luck with the lab report!

    February 5 at 11:51pm · Like
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