Επιστήμη

[_Lloyd]

Pac-Mecium: Το πραγματικό Pac-Man με μικροοργανισμούς!

Post επιστήμης που αφορά στα videogames. It must be the nerdiest post ever.

[NickTG]

Δύο ωραία animation για το πως δουλεύει ένας κινητήρας από Ford και Nissan:

Ένα animation από περιστροφικό κινητήρα. Μόνο το RX-8 της Mazda χρησιμοποιεί κινητήρα περιστροφικού τύπου(μιλώντας πάντα για αυτοκίνητα):

Το νέο σύστημα multiair από την FPT(fiat powertrain technologies):

Και ένα μπόνους που μάλλον έπρεπε να μπει στην τέχνη. Η κατασκευή ενός V12 από τη Ferrari:

[Koul]

Την μηχανή wankel άν δέν κάνω λάθος την χρησιμοποιούν και άλλα mazda όπως το rx-7. Απ ότι ξέρω καλύτερες επιδόσεις λιγότερος χρόνος ζωής, τρελή πατέντα.

[NickTG]

Μιλάω για αυτοκίνητα που είναι τώρα σε παραγωγή.

[NickTG]

The final part of Professor Jim Al-Khalili's documentary series about the basic building block of our universe, the atom.
Al-Khalili explores how studying the atom forced us to rethink the nature of reality itself, encountering ideas that seem like they are from science fiction but in fact are a central part of modern science. He discovers that there might be parallel universes in which different versions of us exist and finds out that empty space is not empty at all, but seething with activity.
The world we think we know - the solid, reassuring world of our senses - turns out to be a tiny sliver of an infinitely weirder and more wonderful universe than we had ever conceived in our wildest fantasies.

[NickTG]

[Somari]

Χαχαχα ΠΟΛΥ ΚΑΛΟ!!! (wink of the day: η αναπαράσταση "πηγαδιών" σε αντιστοιχία με δυναμικά)

[NickTG]

NASA's Gravity Probe B Confirms Two Einstein Space-Time Theories

NASA's Gravity Probe B (GP-B) mission has confirmed two key predictions derived from Albert Einstein's general theory of relativity, which the spacecraft was designed to test. The experiment, launched in 2004, used four ultra-precise gyroscopes to measure the hypothesized geodetic effect, the warping of space and time around a gravitational body, and frame-dragging, the amount a spinning object pulls space and time with it as it rotates. GP-B determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth.

http://www.nasa.gov/mission_pages/gpb/gpb_results.html

[Somari]

Βασικά άφησες έξω το πιο ουσιώδες κομμάτι

GP-B determined both effects with unprecedented precision by pointing at a single star, IM Pegasi, while in a polar orbit around Earth. If gravity did not affect space and time, GP-B's gyroscopes would point in the same direction forever while in orbit. But in confirmation of Einstein's theories, the gyroscopes experienced measurable, minute changes in the direction of their spin, while Earth's gravity pulled at them.

[NickTG]

Ήταν σε άλλη σελίδα η εισαγωγή που έβαλα.

[Somari]

Καλά όχι ότι χρειάζοταν επιβεβαίωση η GR, αφού την απέδειξε ο ίδιος ο Αϊνστάιν κατά τη διάρκεια της περίφημης έκλειψης. Είναι σαν να περιμέναμε αυτό το πείραμα να αποδείξει την θεωρία του Γαλιλέου :

[NickTG]

Τώρα όμως δεν μπορεί κανείς να φέρει αντίρρηση.

[Somari]

Oύτε πριν θα μπορούσαν, είχε αποδειχθεί και πειραματικά, όχι μόνο στα χαρτιά... και ας υπαρχουν site σαν το www.tsolkas.gr

[NickTG]

Είναι αλλιώς όμως τα high tech πειράματα. :resp:

[Ramparter]

Για βοηθηστε λιγο για το παρακατω να καταλαβουμε και οι muggles...

http://www.neogaf.com/forum/showthread.php?t=430761

BBC: New method 'confirms dark energy'

First results from a major astronomical survey have confirmed the existence of mysterious dark energy using a cutting-edge technique.

Dark energy makes up some 74% of the Universe and its existence explains why the Universe appears to be expanding at an accelerating rate.

The finding was based on studies of more than 200,000 galaxies.

Scientists used two separate kinds of observation to provide an independent check on previous dark energy results.

Two papers by an international team of researchers have been accepted for publication in the Monthly Notices of the Royal Astronomical Society journal.

One type of observation used by the astronomers involves measuring a pattern in how galaxies are distributed in space. This pattern is known by the term "baryon acoustic oscillations".

The second type of observation involves measuring how quickly clusters of galaxies have formed over time. Both of these techniques confirmed the existence of dark energy and the acceleration in the expansion of the Universe.

The concept of dark energy was first invoked in the late 1990s by studying the brightness of distant supernovas - exploding stars.

Einstein was right

To explain why the expansion of the Universe was speeding up, astronomers had to either rewrite Albert Einstein's theory of gravity or accept that the cosmos was filled with a novel type of energy.

"The action of dark energy is as if you threw a ball up in the air, and it kept speeding upward into the sky faster and faster," said co-author Dr Chris Blake of the Swinburne University of Technology in Melbourne, Australia.

"The results tell us that dark energy is a cosmological constant, as Einstein proposed. If gravity were the culprit, then we wouldn't be seeing these constant effects of dark energy throughout time."

The latest findings have come from a galaxy survey project called WiggleZ, which began in 2006 and finished this year. WiggleZ used data from Nasa's Galaxy Evolution Explorer (Galex) space telescope and the Anglo-Australian Telescope on Siding Spring Mountain in Australia.

The survey mapped the distribution of galaxies in an unprecedented volume of the Universe, looking eight billion years back in time - more than half the age of the Universe.

Cosmologist Bob Nicholl, who was not involved with the research, told BBC News: "This is a major step forward. These guys are serious, major scientists and we've been waiting for this result for some time.

The professor of astrophysics at Portsmouth University, UK, added: "It's re-confirmation of dark energy, it gives us another data point to fit our theories around and it shows us the way to the future. More astronomers are going to be doing this in years to come."

While dark energy makes up about 74% of the Universe, dark matter - which does not reflect or emit detectable light - accounts for 22%. Ordinary matter - gas, stars, planets and galaxies - makes up just 4% of the cosmos.

However, despite scientists being able to infer the existence of dark energy and dark matter, these phenomena still elude a full explanation.

Dark Energy is real

http://www.aao.gov.au/press/wigglez2011/


Observations of more than 200,000 galaxies made with the Anglo-Australian Telescope in eastern Australia have shown that "dark energy" is real and not a mistake in Einstein's conception of gravity.

The result is conveyed in two papers written by Dr Chris Blake (Swinburne University of Technology, Melbourne, Australia) and colleagues, which have been accepted for publication in the journal Monthly Notices of the Royal Astronomical Society.

The galaxy survey, called WiggleZ ("wiggles"), was set up to measure the properties of "dark energy", a concept invoked in the late 1990s to explain why the Universe seems to be expanding at an accelerating rate.

To account for the acceleration, astronomers had to either rewrite Einstein's theory of gravity or accept that the Universe is filled with a new kind of energy.

"Our new work shows dark energy is real," said Dr Blake. "Einstein remains untoppled."

Dark energy was originally discovered by studying the brightness of distant supernovae — exploding stars.

The WiggleZ project has used two other kinds of observations that provide an independent check on the supernovae results. One kind involves measuring a pattern in how galaxies are distributed in space ("baryon acoustic oscillations"), and the other, measuring how quickly clusters of galaxies have formed over time. [For details, see Background Notes, below.]

Both tests have confirmed the reality of dark energy.

WiggleZ is one of several baryon acoustic oscillations experiments planned or in progress, and is the first one at high redshift to bear significant fruit.

The survey mapped the distribution of galaxies in an unprecedented volume of the Universe, looking eight billion years back in time — more than half the age of the Universe.

"This is the first individual galaxy survey to span such a long stretch of cosmic time," said Professor Michael Drinkwater (University of Queensland), one of the survey's leaders. "We've broken new ground."

Professor Matthew Colless is Director of the Australian Astronomical Observatory, which operates the Anglo-Australian Telescope, and a member of the WiggleZ team. "WiggleZ has been a success because we have an instrument attached to the telescope, a spectrograph, that is one of the best in the world for large galaxy surveys of this kind," he said.

The survey, which began in 2006 and finished this year, was led by Professor Warrick Couch of Swinburne University of Technology in Melbourne and Professor Michael Drinkwater of the University of Queensland. Dr Chris Blake has led the analysis of the survey results.

The Australian Astronomical Observatory is Australia's national optical observatory, and is part of the Commonwealth Department of Innovation, Industry, Science and Research. It operates the 3.9-m Anglo-Australian Telescope and the 1.2-m UK Schmidt Telescope at Siding Spring Observatory in New South Wales, Australia.