#friedmann

Mamás Friedmann, csálé gyertyával.

The Most Important Equation In The Universe

"The first Friedmann equation describes how, based on what is in the universe, its expansion rate will change over time. If you want to know where the Universe came from and where it's headed, all you need to measure is how it is expanding today and what is in it. This equation allows you to predict the rest!"

In 1915, Einstein put forth General Relativity as a new theory of gravity. It reproduced all of Newton’s earlier successes, solved the problem that Newton couldn’t of Mercury’s orbit, and made a new prediction of bent starlight by large masses, verified during the 1919 solar eclipse. Despite the fact that it included a cosmological constant to keep the Universe static, that didn’t deter Soviet physicist Alexander Friedmann from solving Einstein’s equations for a Universe that was filled with matter and energy, all the way back in 1922. The two generic equations he found, known as the Friedmann equations, immediately related measurable quantities like the amount of matter in the Universe to the expansion or contraction rate, which just years later became validated by Hubble’s observations. But the young Friedmann never lived to see it; he died of typhoid fever contracted when he was returning from his honeymoon in 1925.

A hozzávalók:

30 dkg (kicsit kevesebb, mint másfél guriga) Győri Édes zabkeksz

10 dkg vaj

15 dkg csoki

1,5 dl tejszín

1 doboz (20 dkg) natúr krémsajt

2 dl tejszín

kb. 50 dkg eper

átlátszó tortazselé a tetejére

1. A zabkekszet ledaráljuk, összekeverjük a vajjal, és 29 cm átmérőjű (én ekkorában készítem, ikeás) piteformában egyenletesen elrendezzük úgy, hogy végig a peremet is fedje a keksz. 180 fokos sütőben 12 percig sütjük, majd kivesszük, hűlni hagyjuk.

2. A csokit összeolvasztjuk (én mikróban) a tejszínnel. Úgy szoktam, hogy egy bögrébe tördelem a csokit, ráöntöm a tejszínt, és kb. másfél percre teszem a mikróba – a tejszín felforr, de ne fusson ki… Utána már csak keverem, amíg a csoki és a tejszín tökéletesen nem elegyedik. A keveréket a kekszalapra öntöm, kihűtöm.

3. Felverjük a tejszínt 2 ek cukorral, majd hozzáadjuk a krémsajtot. Eloszlatjuk a csokin.

4. Az epret felszeleteljük, szépen elrendezzük a sajtos krémen, majd befedjük a leírásnak megfelelően elkészített tortazselével.

Minden így, csak cm tk Kekszből, eper helyett málnával és Dr.Oetker expressz zselatinnal.

Ask Ethan: If the Universe is expanding, why aren’t we?

“If the universe is expanding at rates in excess of the speed of light, why does it not appear to affect our solar system and the planetary distances from the sun, etc.? And why would the relative distances of stars in our galaxy not appear to be increasing... or are they?”

It's a thing of scientific beauty that we've not only been able to determine that the Universe is expanding, but that we've been able to measure the rate of expansion so incredibly well. To better than 90% uniformity, we've determined the expansion rate in all directions and going back billions of years, allowing us to determine what's in the Universe, how that's changed over time, and what its fate is. It's one of the most remarkable achievements of modern science over the last 100 years. But even though the distant galaxies are all expanding away both from us and from one another, not everything in the Universe is expanding. Individual galaxy clusters remain bound; galaxies do not grow; planetary orbits remain constant; stars, planets, humans and even atoms remain the same size. Yet, the fabric of the Universe itself still continues to expand.