From boud w astro.uni.torun.pl Thu Oct 2 15:08:29 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Thu, 2 Oct 2003 15:08:29 +0200 (CEST) Subject: Shape of the Universe IV+V rok monograph course 15:15 today ! Message-ID: Cześć wszystkim, The teaching responsibilities that Andrzej Strobel offered to me are presented here: http://adjani.astro.uni.torun.pl/cgi-bin/twiki/view/Cosmo/CosmoTeaching20032004 ** Monograph course: It seems that the IV+V monograph course officially starts today (czwartek 02.10.2003) at 15:15 in the Radio building. Anyone interested please come along today and/or subscribe to the shape-univ mailing list: SUBSCRIBE: email to sympa w astro.uni.torun.pl with "subscribe shape-univ" ** "IV+V Seminar": This is compatible with CafePlus, but 17:00 czwartek is clearly not the best time. Day/time: You can join the cosmo-spotka mailing list for trying to find the best day/time for this. Place: It would be best to alternate between Piwnice (radio building) and CAMK (rabiańska). SUBSCRIBE: email to sympa w astro.uni.torun.pl with "subscribe cosmo-spotka" Proszę odpowiedź do: cosmo-spotka at astro.uni.torun.pl pozdrawiam boud From ab_cha w 123.com Wed Oct 22 05:25:21 2003 From: ab_cha w 123.com (Alhaja Mariam Abacha) Date: Tue, 21 Oct 2003 20:25:21 -0700 Subject: regards Message-ID: <200310220321.h9M3LU6o027121@newton.astro.uni.torun.pl> Dear friend, A very Good day to you.I am by name,Alhaja mariam sani Abacha,the former firstlady and also the wife of the former late head of state of the federal republic of Nigeria,Late Gen.Sani Abacha whose sudden death came on the 8th of June,1998.Since his death,I have been thrown into a state of utter confusion, frustration and hopelessness by the present civilian administration, I have been subjected tophysical and psychological torture by the security agents in the country. My son Mohammed was under detention arraigned before the federal high court of Nigeria for an offence he did not commit.Though he has been released since on the 23rd of september,2002 based on certain conditions,but he is not allowed to move around to any where.He has been restricted to his own town only and also been placed under the government watch.As a widow that is so traumatized, I have lost confidence with anybody within the country. You must have heard over the media reports and the internet on the recovery of various huge sums of money deposited by my husband in different security firms abroad, some companies willingly gave up their secrets and disclosed our money confidently lodged there while many out right blackmail. In fact the total sum discovered by the government so far is in the tune of$700.Million dollars. And they are not relenting to make me poor for life. I got your contacts through my personal research,and out of desperation decided to reach you through this medium.I will give you more information as to this regard as soon as you reply. I repose great confidence in you hence my approach to you dueto security network placed on my day to day affairs I cannot afford to visit the embassy so that is why I decided to contact you and I hope you will not betray my confidence in you. I have deposited the sum of $30 million dollars with a security firm abroad whose name is witheld for now until we open communication. I shall be grateful if you could receive this fund into your account for safe keeping. This arrangement is known to you and my son Abba alone, so my son will deal directly with you as security is up my wholebeing.I am seriously considering to settle down abroad in a friendly atmosphere like yours as soon as this fund get into your account so that I can start all over again if only you wish,but if it is impossible,just help me keep this funds in your account which will accrue you 30% of this fund . Please honesty is the watch word in this transaction.I will require your telephone and fax numbers so that we can commence communication immediately and I will give you a more detail picture of things.In case you don`t accept please do not let me out to the security as I am giving ou this information in total trust and confidence, I ill greatly appreciate if you accept my proposal in good faith.Please expedite action. Sincerely yours, Alhaja Mariam Abacha. From boud w astro.uni.torun.pl Wed Oct 22 17:51:42 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Wed, 22 Oct 2003 17:51:42 +0200 (CEST) Subject: nastepny wyklad monograficzny czwartek 30.10.2003 (nie jutro!) Message-ID: http://adjani.astro.uni.torun.pl/cgi-bin/twiki/view/Cosmo/MonographCosmo jest seminar (cafeplus) jutro, ale nie ma wyklad monograficzny. pozd boud From boud w astro.uni.torun.pl Thu Oct 30 09:33:47 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Thu, 30 Oct 2003 09:33:47 +0100 (CET) Subject: pamietamy: wyklad monog dzis *w sal komputerze KA&A* !!! Message-ID: witam, pamietamy: wykład monog dziś 30.10.2003 *w sal komputerze KA&A* na 15.15 pozd boud http://adjani.astro.uni.torun.pl/cgi-bin/twiki/view/Cosmo/MonographCosmo From szajtan w poczta.onet.pl Sun Oct 5 23:53:57 2003 From: szajtan w poczta.onet.pl (szajtan odwieczny) Date: Sun, 5 Oct 2003 23:53:57 +0200 (CEST) Subject: l_p ~ \Omega_tot^-1/2 Message-ID: for those who are not in the topic it is about the question why is l_p (which is the number of the multipole on which there is the first peak - so called acustic peak - in the angular power spectrum of CMB fluctuations) proportional to \Omega_tot^-1/2 (which is the unitless total density of the Universe) ? Lately I was thinking about such explanation but don't know if this mae be correct. l_p \approx EH_LSS / SH_LSS where EH_LSS is (say *) the event horizon at the time of last scattering and SH_LSS is the sonic horizon at the last scattering (t=t_LSS). EH_LSS = c * \int_{t_LSS}^{t_0} dt/S(t) SH_LSS = c_s * \int_{0}^{t_LSS} dt/S(t) where c - speed of light, c_s - speed of sound, S(t) - is scale factor. So it's just the angle under which today we see the sonic horizon as it was at the time of last scattering. so from the above it would be that: l_p ~ c_s^-1 (~ means "proportional" here) the speed of sound is defined by: c_s = \sqrt{ (P/\rho)_S } (while entropy - S is constant) (P- pressure, \rho - density) for adiabatic transformation the entropy is or mae be conserved and the equation of state is: P\rho^-\gamma = const where \gamma is the adiabatic index So in short we have c_s ~ \rho^{ (\gamma - 1)/2 } and thus l_p ~ \rho^{ (1-\gamma)/2 } ~ \Omega_{tot}^{ (1-\gamma)/2 } so if the adiabatic index gamma for primordinal plasma is 2 then this consideration mae answer the quiestion, however gamma for nonrelatistic, in moderate temperatures, single-atom gases is something like 1.67 - not 2. Don't know how it is with hydrogen plasma in temperature of few thousand K. Any comments much appreciated. like it might be ok. or this is complete nonsense. ------------ Boud: * - this is the comment about the event horizon. sure that the event horizon is the maximal distance from which, say some light, will ever reach us - and because of that I agree there should be infinity in the top limit of integration in the above formula for event horizon, but I guess if it comes about the event horizon at the time t=t_LSS then wheather there is \infty or just t=t_0 doesn't change the integral much, because from the t=t_LSS point of view the time like 14,2*10^9 y is like infinity. (Because the cones of light of some simultanous events at the time t_LSS drown in "normal" (proper ?) coordinates (not comoving) which are separated (the events) by the distance of event hirizon at the time t=t_LSS, become almost paralel.**) So in other words the size of the event horizon given by the above formula will probably be just a little smaller than the real event horizon at the time in case when integrated to infinity. bart. ----- btw. It is interesting that: If calculate l_p for dust universe where S(t) ~ t^2/3 it is easy to show that l_p \approx 35,2 * c/c_s and thus for l_p=220 where it is observed, we see that at the time of last scattering the sound of speed was about 6,25 times smaller than the speed of light which sounds resonable ;) (oh, this is for flat univ.) ** - this requires some more work to think, and mae be not precise explanation. From boud w astro.uni.torun.pl Mon Oct 6 16:33:15 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Mon, 6 Oct 2003 16:33:15 +0200 (CEST) Subject: l_p ~ \Omega_tot^-1/2 In-Reply-To: References: Message-ID: On Sun, 5 Oct 2003, szajtan odwieczny wrote: > for those who are not in the topic it is about the question > why is l_p (which is the number of the multipole on which there is the > first peak - so called acustic peak - in the angular power spectrum of CMB > fluctuations) proportional to \Omega_tot^-1/2 (which is the unitless total > density of the Universe) ? Maybe Ruth Durrer's paper "The theory of CMB anisotropies" might help? http://arxiv.org/abs/astro-ph/0109522 e.g. p26 From michalf w ncac.torun.pl Wed Oct 8 00:11:14 2003 From: michalf w ncac.torun.pl (Michal Frackowiak) Date: Wed, 08 Oct 2003 00:11:14 +0200 Subject: l_p ~ \Omega_tot^-1/2 In-Reply-To: References: Message-ID: <3F833A02.2000604@ncac.torun.pl> 1. PLEASE attach a .ps or a .pdf if you are going to present many formulas!!!! hard to render them on-the-fly and... why? 2. "why is l_p proportional to \Omega_tot^-1/2" it is not. it is an old formula for a matter-dominated universe as I remember. forget it. some people still use it (peacock). dig some ads or astro-ph stuff. 3. sonic speed in the relativistic plasma is c/sqrt{3}. right? ;-) BUT: c_s is NOT constant at that time. it is not that easy and I would rather start with learning what people have already done than playing hide-and-seek with numbers. THESE QUESTIONS ARE ALREADY ANSWERED ;-) - and answers were applied to soft such as CMBfast which you use often ;-) regards - michal f szajtan odwieczny wrote: >for those who are not in the topic it is about the question >why is l_p (which is the number of the multipole on which there is the >first peak - so called acustic peak - in the angular power spectrum of CMB >fluctuations) proportional to \Omega_tot^-1/2 (which is the unitless total >density of the Universe) ? > >Lately I was thinking about such explanation but don't know if this mae be >correct. > >l_p \approx EH_LSS / SH_LSS >where EH_LSS is (say *) the event horizon at the time of last scattering >and >SH_LSS is the sonic horizon at the last scattering (t=t_LSS). > >EH_LSS = c * \int_{t_LSS}^{t_0} dt/S(t) >SH_LSS = c_s * \int_{0}^{t_LSS} dt/S(t) > >where c - speed of light, c_s - speed of sound, S(t) - is scale factor. >So it's just the angle under which today we see the sonic horizon as it >was at the time of last scattering. > >so from the above it would be that: > >l_p ~ c_s^-1 (~ means "proportional" here) > >the speed of sound is defined by: > >c_s = \sqrt{ (P/\rho)_S } (while entropy - S is constant) >(P- pressure, \rho - density) > >for adiabatic transformation the entropy is or mae be conserved and the >equation of state is: > >P\rho^-\gamma = const >where \gamma is the adiabatic index > >So in short we have > >c_s ~ \rho^{ (\gamma - 1)/2 } > >and thus > >l_p ~ \rho^{ (1-\gamma)/2 } ~ \Omega_{tot}^{ (1-\gamma)/2 } > >so if the adiabatic index gamma for primordinal plasma is 2 then this >consideration mae answer the >quiestion, however gamma for nonrelatistic, in moderate temperatures, >single-atom gases is something like 1.67 - not 2. Don't know how it is >with hydrogen plasma in temperature of few thousand K. > >Any comments much appreciated. like it might be ok. or this is complete >nonsense. >------------ >Boud: > >* - this is the comment about the event horizon. > >sure that the event horizon is the maximal distance from which, say >some light, will ever reach us - and because of that I agree there should >be infinity in the top limit of integration in the above formula for event >horizon, but I guess if it comes about the event horizon at the time >t=t_LSS then wheather there is \infty or just t=t_0 doesn't change the >integral much, because from the t=t_LSS point of view the time like >14,2*10^9 y is like infinity. (Because the cones of light of some >simultanous events at the time t_LSS drown in "normal" (proper ?) >coordinates (not comoving) which are separated (the events) by the >distance of event hirizon at the time t=t_LSS, become almost paralel.**) >So in other words the size of the event horizon given by the above >formula will probably be just a little smaller than the real event horizon >at the time in case when integrated to infinity. > >bart. >----- > >btw. It is interesting that: > >If calculate l_p for dust universe where S(t) ~ t^2/3 >it is easy to show that >l_p \approx 35,2 * c/c_s >and thus for l_p=220 where it is observed, we see that at the time of last >scattering the sound of speed was about 6,25 times smaller than the speed >of light which sounds resonable ;) (oh, this is for flat univ.) > > >** - this requires some more work to think, and mae be not precise >explanation. > > > > > >------------------------------------------------------------------------ > >LISTNAME: shape-univ >HELP: send an email to sympa w astro.uni.torun.pl with "help" >WEB ARCHIVE: http://www.astro.uni.torun.pl/sympa/shape-univ/ >UNSUBSCRIBE: email to sympa w astro.uni.torun.pl with "unsubscribe shape-univ" > > > > From boud w astro.uni.torun.pl Wed Oct 8 18:49:22 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Wed, 8 Oct 2003 18:49:22 +0200 (CEST) Subject: l_p ~ \Omega_tot^-1/2 In-Reply-To: <3F833A02.2000604@ncac.torun.pl> References: <3F833A02.2000604@ncac.torun.pl> Message-ID: cześć, On Wed, 8 Oct 2003, Michal Frackowiak wrote: > 1. PLEASE attach a .ps or a .pdf if you are going to present many > formulas!!!! hard to render them on-the-fly and... why? Or write them to a scratch TWiki page linked from http://adjani.astro.uni.torun.pl/cosmo with %$\int_{-\infty}^\infty e^{-\alpha x^2} dx$% i.e. using %$ latex expression $% > > 2. "why is l_p proportional to \Omega_tot^-1/2" > it is not. it is an old formula for a matter-dominated universe as I > remember. forget it. some people still use it (peacock). dig some ads or > astro-ph stuff. > > 3. sonic speed in the relativistic plasma is c/sqrt{3}. right? ;-) BUT: > c_s is NOT constant at that time. it is not that easy and I would rather > start with learning what people have already done than playing > hide-and-seek with numbers. > > THESE QUESTIONS ARE ALREADY ANSWERED ;-) - and answers were applied to > soft such as CMBfast which you use often ;-) In other words, "dig some ads or astro-ph or CMBfast code". ;) Certainly learning what other people have already done is a good idea - but being skeptical about it is also useful and helps in understanding. E.g.: http://arxiv.org/abs/astro-ph/0310186 Cosmological parameters and the WMAP data Authors: Antony Lewis which supports the claim that the WMAP data is not as easy to interpret as is claimed by the official team... pozd boud > regards - michal f > > szajtan odwieczny wrote: > > >for those who are not in the topic it is about the question > >why is l_p (which is the number of the multipole on which there is the From szajtan w priv.onet.pl Wed Oct 8 18:48:57 2003 From: szajtan w priv.onet.pl (Szajtan Odwieczny) Date: Wed, 8 Oct 2003 18:48:57 +0200 (CEST) Subject: l_p ~ \Omega_tot^-1/2 In-Reply-To: <3F833A02.2000604@ncac.torun.pl> Message-ID: > 1. PLEASE attach a .ps or a .pdf if you are going to present many > formulas!!!! hard to render them on-the-fly and... why? ok > > 2. "why is l_p proportional to \Omega_tot^-1/2" > it is not. it is an old formula for a matter-dominated universe as I > remember. forget it. some people still use it (peacock). dig some ads or > astro-ph stuff. hmm a) then what is the use of such mailing list, if everybody can find and learn everything by himself ? I presume this stuff is been already done by someone before and I do not claim to discover anything new (in that case I'd post on cosmo-torun,poland or world ;) or stright to the nobel foundation ;) ) but this is much faster to learn this way than when you're on your own. I seek answers everywhere. btw the article by Ruth Durrer astro-ph/0109522 is very teaching and usefull. thanks b) if all old formulas were to be forgotten then astronomy would fall apart. so the proportion is valid only for universe with \Omega_m = \Omega_tot = 1 or so ? But why ? Sure the position of the peak is related to the density of matter, but in LCDM models if we variate Omega_m then Omega_tot also changes at given \Omega_l, so I see no obstacles for the proportion to work even with nonzero cosmological constant. As I remember well, k-split of the CMBFAST works this way, to speed up the calcutations, that it just shifts (and compreses or stretches) the precalculated spectrum left or right just to satisfy the given curvature, so given \Omega-tot and thus \Omega_m for arbitrary \Omega_l :) but perhaps these are only projeciton effects in spaces of different curvature > > 3. sonic speed in the relativistic plasma is c/sqrt{3}. right? ;-) BUT: don't know but looks suspicious to me (where are densities) :) > c_s is NOT constant at that time. it is not that easy and I would rather > start with learning what people have already done than playing > hide-and-seek with numbers. > THESE QUESTIONS ARE ALREADY ANSWERED ;-) - and answers were applied to > soft such as CMBfast which you use often ;-) d) does it mean we should treat it as some kind of black box, into which we put some parameters from one side , and from the other we see what shape of the spectrum comes out, with none a scant of related mathmatics whatsoever ? i like to know what is at least the general physical explanation that the spectra responds in this way or the other for some cosmological parameter variation. I just noticed that the equation of state I used is like for baryonic gas, not necessary as for CDM. ;) aha ! maeybe that's it ;) in fact barions do not really shift the peak, they only change it's height. anyway there are still many open threads to follow. bart. > > regards - michal f > > szajtan odwieczny wrote: > > >for those who are not in the topic it is about the question > >why is l_p (which is the number of the multipole on which there is the > >first peak - so called acustic peak - in the angular power spectrum of CMB > >fluctuations) proportional to \Omega_tot^-1/2 (which is the unitless total > >density of the Universe) ? > > > >Lately I was thinking about such explanation but don't know if this mae be > >correct. > > > >l_p \approx EH_LSS / SH_LSS > >where EH_LSS is (say *) the event horizon at the time of last scattering > >and > >SH_LSS is the sonic horizon at the last scattering (t=t_LSS). > > > >EH_LSS = c * \int_{t_LSS}^{t_0} dt/S(t) > >SH_LSS = c_s * \int_{0}^{t_LSS} dt/S(t) > > > >where c - speed of light, c_s - speed of sound, S(t) - is scale factor. > >So it's just the angle under which today we see the sonic horizon as it > >was at the time of last scattering. > > > >so from the above it would be that: > > > >l_p ~ c_s^-1 (~ means "proportional" here) > > > >the speed of sound is defined by: > > > >c_s = \sqrt{ (P/\rho)_S } (while entropy - S is constant) > >(P- pressure, \rho - density) > > > >for adiabatic transformation the entropy is or mae be conserved and the > >equation of state is: > > > >P\rho^-\gamma = const > >where \gamma is the adiabatic index > > > >So in short we have > > > >c_s ~ \rho^{ (\gamma - 1)/2 } > > > >and thus > > > >l_p ~ \rho^{ (1-\gamma)/2 } ~ \Omega_{tot}^{ (1-\gamma)/2 } > > > >so if the adiabatic index gamma for primordinal plasma is 2 then this > >consideration mae answer the > >quiestion, however gamma for nonrelatistic, in moderate temperatures, > >single-atom gases is something like 1.67 - not 2. Don't know how it is > >with hydrogen plasma in temperature of few thousand K. > > > >Any comments much appreciated. like it might be ok. or this is complete > >nonsense. > >------------ > >Boud: > > > >* - this is the comment about the event horizon. > > > >sure that the event horizon is the maximal distance from which, say > >some light, will ever reach us - and because of that I agree there should > >be infinity in the top limit of integration in the above formula for event > >horizon, but I guess if it comes about the event horizon at the time > >t=t_LSS then wheather there is \infty or just t=t_0 doesn't change the > >integral much, because from the t=t_LSS point of view the time like > >14,2*10^9 y is like infinity. (Because the cones of light of some > >simultanous events at the time t_LSS drown in "normal" (proper ?) > >coordinates (not comoving) which are separated (the events) by the > >distance of event hirizon at the time t=t_LSS, become almost paralel.**) > >So in other words the size of the event horizon given by the above > >formula will probably be just a little smaller than the real event horizon > >at the time in case when integrated to infinity. > > > >bart. > >----- > > > >btw. It is interesting that: > > > >If calculate l_p for dust universe where S(t) ~ t^2/3 > >it is easy to show that > >l_p \approx 35,2 * c/c_s > >and thus for l_p=220 where it is observed, we see that at the time of last > >scattering the sound of speed was about 6,25 times smaller than the speed > >of light which sounds resonable ;) (oh, this is for flat univ.) > > > > > >** - this requires some more work to think, and mae be not precise > >explanation. > > > > > > > > > > > >------------------------------------------------------------------------ > > > >LISTNAME: shape-univ > >HELP: send an email to sympa w astro.uni.torun.pl with "help" > >WEB ARCHIVE: http://www.astro.uni.torun.pl/sympa/shape-univ/ > >UNSUBSCRIBE: email to sympa w astro.uni.torun.pl with "unsubscribe shape-univ" > > > > > > > > > > > From boud w astro.uni.torun.pl Fri Oct 10 17:14:08 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Fri, 10 Oct 2003 17:14:08 +0200 (CEST) Subject: Dodecahedral space topology In-Reply-To: References: <200310090758.JAA09445@galileo.astro.uni.torun.pl> Message-ID: here's the full article: http://arxiv.org/abs/astro-ph/0310253 On Thu, 9 Oct 2003, Boud Roukema wrote: > On Thu, 9 Oct 2003, Andrzej Marecki wrote: > > > ----- Forwarded message from NatureAlert ----- > > > > [...] > > > > Dodecahedral space topology as an explanation for weak wide-angle > > temperature correlations in the cosmic microwave background > > JEAN-PIERRE LUMINET, JEFFREY R. WEEKS, ALAIN RIAZUELO, ROLAND LEHOUCQ > > & JEAN-PHILIPPE UZAN > > http://info.nature.com/cgi-bin24/DM/y/eMJG0BfWLH0Ch0EeW0Ay > From boud w astro.uni.torun.pl Sat Oct 18 12:57:03 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Sat, 18 Oct 2003 12:57:03 +0200 (CEST) Subject: nowy dzien/godzin wyklad monogr: pon. 16.10-17.40 Message-ID: Witam, Czwartek była propozycja nowa dzień/godz wykład monograficzne: każdy poniedziałek 16.10-17.40 Proszę zobacz: http://adjani.astro.uni.torun.pl/cgi-bin/twiki/view/Cosmo/MonographCosmo pozd boud From boud w astro.uni.torun.pl Sat Oct 18 13:23:16 2003 From: boud w astro.uni.torun.pl (Boud Roukema) Date: Sat, 18 Oct 2003 13:23:16 +0200 (CEST) Subject: nowy dzien/godzin wyklad monogr: pon. 16.10-17.40 In-Reply-To: References: Message-ID: Przepraszam dla pisać drugie raz, ale nie był jasny jeśli to tylko propozycja albo decyzja! Moim skromnym zdaniem, moĹźemy zrobić tym typu decyzji w wykładzie, więc jest decyzja. Dla lepszy rozumieć metoda ,,konsensus" dla podejmowanie decyzji, zobacz: http://www.wikipedia.org/wiki/Consensus_decision_making na poniedziałku @16.10 @KRA pozd boud On Sat, 18 Oct 2003, Boud Roukema wrote: > Witam, > Czwartek byÂła propozycja nowa dzieĂą/godz wykÂład monograficzne: > > kaÂżdy poniedziaÂłek 16.10-17.40 > > ProszĂŞ zobacz: > http://adjani.astro.uni.torun.pl/cgi-bin/twiki/view/Cosmo/MonographCosmo > > pozd > boud > > > >