Există viaţă după moarte - argumentarea unor specialişti în fizică

[AlinB]

În prealabil postat de iuliu46

cand vezi cuvantul geocentrism e normal sa te cutremuri, pentru ca ai fost educat asa. Dar asa cum spune si Hawking nu exista nici o dovada impotriva, doar opinia lor ca nu e nimic special cu Pamantul. Si cand esti ateu e normal sa gandesti asa. Nu e normal atunci cand crezi in Dumnezeu.

Uite ca sa-ti mai actualizezi nitel informatiile si sa nu te mai cutremuri asa usor si mai ales din astfel de motive:

In 1929 Edwin Hubble announced that he had measured the speed of galaxies at different distances from us, and had discovered that the farther they were, the faster they were receding. This might suggest that we are at the centre of the expanding universe, but in fact if the universe is expanding uniformly according to Hubble's law, then it will appear to do so from any vantage point.

If we see a galaxy B receding from us at 10,000 km/s, an alien in galaxy B will see our galaxy A receding from it at 10,000 km/s in the opposite direction. Another galaxy C twice as far away in the same direction as B will be seen by us as receding at 20,000 km/s. The alien will see it receding at 10,000 km/s:
A B C
From A 0 km/s 10,000 km/s 20,000 km/s
From B -10,000 km/s 0 km/s 10,000 km/s


So from the point of view of the alien at B, everything is expanding away from it, whichever direction it looks in, just the same as it does for us.
The Famous Balloon Analogy

A good way to help visualise the expanding universe is to compare space with the surface of an expanding balloon. This analogy was used by Arthur Eddington as early as 1933 in his book The Expanding Universe. It was also used by Fred Hoyle in the 1960 edition of his popular book The Nature of the Universe. Hoyle wrote "My non-mathematical friends often tell me that they find it difficult to picture this expansion. Short of using a lot of mathematics I cannot do better than use the analogy of a balloon with a large number of dots marked on its surface. If the balloon is blown up the distances between the dots increase in the same way as the distances between the galaxies."

The balloon analogy is very good but needs to be understood properly—otherwise it can cause more confusion. As Hoyle said, "There are several important respects in which it is definitely misleading." It is important to appreciate that three-dimensional space is to be compared with the two-dimensional surface of the balloon. The surface is homogeneous with no point that should be picked out as the centre. The centre of the balloon itself is not on the surface, and should not be thought of as the centre of the universe. If it helps, you can think of the radial direction in the balloon as time. This was what Hoyle suggested, but it can also be confusing. It is better to regard points off the surface as not being part of the universe at all. As Gauss discovered at the beginning of the 19th century, properties of space such as curvature can be described in terms of intrinsic quantities that can be measured without needing to think about what it is curving in. So space can be curved without there being any other dimensions "outside". Gauss even tried to determine the curvature of space by measuring the angles of a large triangle between three hill tops.

When thinking about the balloon analogy you must remember that. . .
The 2-dimensional surface of the balloon is analogous to the 3 dimensions of space.
The 3-dimensional space in which the balloon is embedded is not analogous to any higher dimensional physical space.
The centre of the balloon does not correspond to anything physical.
The universe may be finite in size and growing like the surface of an expanding balloon, but it could also be infinite.
Galaxies move apart like points on the expanding balloon, but the galaxies themselves do not expand because they are gravitationally bound.

http://math.ucr.edu/home/baez/physic...GR/centre.html

Cam complicat? Desigur, geocentrismul e mult mai simplu.
Sau ideea lui vsovi ca pamantul e plat si cerul e de fapt un soi de acoperis iar stelele gauri in el.
Sigur, ai libertatea sa optezi pentru oricare varianta, succes

[iuliu46]

În prealabil postat de AlinB

Uite ca sa-ti mai actualizezi nitel informatiile si sa nu te mai cutremuri asa usor si mai ales din astfel de motive:

...
Sigur, ai libertatea sa optezi pentru oricare varianta, succes

La ce era nevoie sa scrii tot carnatul ala ? Trimite-l lui Hawking si spune-i lui ca ai gasit tu dovada ca povestea cu balonul e adevarata. Sau lui George Ellis. Probabil ei nu au apucat sa citeasca pe site-ul ala si ti-ar fi recunoscatori.

[AlinB]

Aha, uite cum apelul la autoritate ne scuteste de un obositor exercitiu mental.

E mai frumos asa, sa selectezi din tot ce auzi doar ce-ti convine, in felul asta nu mai e nevoie sa gandesti, chestie dificila si nu tocmai la moda, acum e mai "cool" sa rostesti un nume decat sa justifici o convingere.

[iuliu46]

În prealabil postat de AlinB

Aha, uite cum apelul la autoritate ne scuteste de un obositor exercitiu mental.

E mai frumos asa, sa selectezi din tot ce auzi doar ce-ti convine, in felul asta nu mai e nevoie sa gandesti, chestie dificila si nu tocmai la moda, acum e mai "cool" sa rostesti un nume decat sa justifici o convingere.

Pai nu e apel la autoritate. Eu inteleg chestia cu balonul si accept ca s-ar putea sa fie adevarata. Dar s-ar putea sa nu fie, aici e problema. Deci la ce bun sa discutam chestia aia ? Tu vii, trantesti un carnat si-mi zici : de ce nu accepti ca asa e ? Pentru ca s-ar putea sa nu fie asa. Indiferent daca imensa majoritate crede ca e asa, eu raman la vorba Ceauseascai : " DOVADA ! ".
Deci sa se duca dansii frumos prin Zeta Reticuli, Alfa Centauri si pe unde mai viseaza sa ajunga si sa ne spuna cum se vede universul de acolo, ca klingonienii, romulanii, cardassienii, ferengi, si reptilienii aia vin mereu in vizita pe la noi. Pe urma mai vorbim.

[iuliu46]

Daca tot ne plac carnatii uite pun si eu unul :

http://www.sciencedaily.com/releases...0926184749.htm

Dark Energy: Is It Merely An Illusion?

Dark energy is at the heart of one of the greatest mysteries of modern physics, but it may be nothing more than an illusion, according physicists at Oxford University.

The problem facing astrophysicists is that they have to explain why the universe appears to be expanding at an ever increasing rate. The most popular explanation is that some sort of force is pushing the accelerating the universe's expansion. That force is generally attributed to a mysterious dark energy.
Although dark energy may seem a bit contrived to some, the Oxford theorists are proposing an even more outrageous alternative. They point out that it's possible that we simply live in a very special place in the universe - specifically, we're in a huge void where the density of matter is particularly low. The suggestion flies in the face of the Copernican Principle, which is one of the most useful and widely held tenets in physics.
Copernicus was among the first scientists to argue that we're not in a special place in the universe, and that any theory that suggests that we're special is most likely wrong. The principle led directly to the replacement of the Earth-centered concept of the solar system with the more elegant sun-centered model.
Dark energy may seem like a stretch, but it's consistent with the venerable Copernican Principle. The proposal that we live in a special place in the universe, on the other hand, is likely to shock many scientists. The maverick physicists at Oxford conclude their paper by pointing out that forthcoming tests of the Copernican principle should help us sort out the mystery in the next few years.


Vezi ce usor e ?

[iuliu46]

Altul :

http://content.usatoday.com/communit.../08/68497142/1

Mystery solved: Dark energy isn't there
...
The only problem is that for the equations to work, we must be "literally at the center of the universe, which is, to say the least, unusual," says physicist Lawrence Krauss of Arizona State University in Tempe. "I think this is plausible mathematics, but it doesn't seem physically relevant."

Deci stai ce ne zic astia in cele 2 articole ? Ca daca pamantul ar fi in mijloc ( ceea ce e imposibil, normal, ca cine sa-l fi pus in mijloc ? :) ) nu am mai avea nevoie nici de chestia asta cu energia neagra ?

[DragosP]

Nişte proşti.

[catalin2]

În prealabil postat de Patrie si Credinta

de fapt sunt din Antichitate. exista un ateism grec antic, unul vechi testamentar(aia cu a zis nebunul). Dar toate au mutatii specifice epocii.

Exact, chiar asta am avut in gand, filozofii materialisti din Grecia antica, atunci cand am scris: "De fapt lumea nu se imparte in credinciosi si atei, ateii au aparut in epoca moderna abia in perioada iluminista."
Am scris de cei din epoca moderna.

[catalin2]

În prealabil postat de bogdan81

Bravo, ai pus punctul pe i.
Suntem speciali si tocmai in acest sens e adevarat geocentrismul : in sensul ca suntem speciali, NU neaparat in sensul fizic.

Geocentrism cred ca se poate referi la doua lucruri: unul, mai cunoscut, ca soarele se invarte in jurul pamantului si altul, ca sistemul solar si pamantul sunt in centrul universului.
Eu nu sustin prima varianta, pentru ca se stie si din observatii directe ca e gresita. Citatul se refera doar la a doua varianta, e evident ca Hawking nu crede ca soarele se invarte in jurul pamantului.
Cautand acum pe net am gasit si un argument mai clar, intr-un articol: http://www.preferatele.com/docs/geog...n-expansi4.php
"Acum, la prima vedere, aceasta dovada ca universul arata acelasi indiferent in ce directie privim ar parea sa sugereze ca exista ceva special in ceea ce priveste locul nostru in univers. Mai ales, ar parea ca daca observam ca toate celelalte galaxii se departeaza de noi; atunci noi trebuie sa fim in centrul universului. Exista, totusi, o alta explicatie; universul poate sa arate la fel in orice directie si vazut din oricare alta galaxie. Aceasta, asa cum am vazut, a fost a doua ipoteza a lui Friedmann. Nu avem o dovada stiintifica pentru sau impotriva acestei ipoteze. O credem datorita modestiei: ar fi fost cu totul extraordinar daca universul ar fi aratat acelasi in orice directie in jurul nostru, si nu in jurul altor puncte din univers! In modelul lui Friedmann, toate galaxiile se departeaza una de alta."

Asadar, ca si in alte dati, sa separam argumentele stiintifice de ipoteze. Stiinta spune ca noi ne-am afla in centrul Universului. Argumentul ca nu e asa se bazeaza pe "modestie", dar modestia nu e argument stiintific. Deci, daca pana acum doar observam ca exista aceatsa ipoteza, cred ca putem spuen ca suntem in centrul Universului, fara sa fie vreun argument impotriva acestui lucur, ba chiar stiinta spune ca e adevarat.

[AlinB]

În prealabil postat de iuliu46

Pai nu e apel la autoritate. Eu inteleg chestia cu balonul si accept ca s-ar putea sa fie adevarata. Dar s-ar putea sa nu fie, aici e problema. Deci la ce bun sa discutam chestia aia ? Tu vii, trantesti un carnat si-mi zici : de ce nu accepti ca asa e ?

Aiurea, n-ai inteles.
Ideea era ca sunt explicatii pentru acele observatii, care nu implica neaparat sf -uri ca geocentrismul.

E drept ca asta implica sa realizezi ca Universul fizic e ceva mai mare si sofisticat decat asa cum se poate vedea cu ochiul liber, dar cred ca e un pas pe care l-ar putea face oricine are un minim de educatie, adica stie macar sa scrie si sa citeasca, nu mai zic de calculator si Internet, desi realitatea mintii umane se pare ca este si ea mai complicata de atat.

Se pare ca ai reflexul romano-catolicilor de acum cateva secole care vroiau musai ca geocentrismul sa triumfe pentru ca altfel, chipurile, pozitia religiosa, intemeiata de fapt mai degraba pe prejudecata, mit si superstitie decat credinta autentica, ar fi fost amenintata.