Path: csiph.com!xmission!news.snarked.org!border2.nntp.dca1.giganews.com!nntp.giganews.com!buffer2.nntp.dca1.giganews.com!nntp.earthlink.com!news.earthlink.com.POSTED!not-for-mail NNTP-Posting-Date: Fri, 16 Mar 2018 23:21:01 -0500 Message-ID: <5AAC97DF.7BBF@ix.netcom.com> Date: Fri, 16 Mar 2018 21:21:51 -0700 From: The Starmaker Reply-To: starmaker@ix.netcom.com X-Mailer: Mozilla 3.04Gold (WinNT; U) MIME-Version: 1.0 Newsgroups: rec.arts.sf.written,sci.physics,sci.physics.relativity,alt.astronomy Subject: Re: Does Intelligent Life Exist On Earth? References: <5AAB611D.47AB@ix.netcom.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Antivirus: Avast (VPS 180316-4, 03/16/2018), Outbound message X-Antivirus-Status: Clean Lines: 38 X-Usenet-Provider: http://www.giganews.com NNTP-Posting-Host: 108.219.229.47 X-Trace: sv3-ax7mC5vwx7C5MMRkS8BPrCq+O9SAJFySuSoQn8MSlkYxxfL7q47jn/PwVbY1WhSVK8t1PPF1VCfzC4W!1EV578daBTPu2WWP344BJv9e9RM7ZH8IBeXHQlsGS8fTdRprmUhYLQlj7QyKzux+W5Zj/E+uPpNQ!hS45/q3S2Lk= X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 3025 Xref: csiph.com rec.arts.sf.written:488646 sci.physics:676770 sci.physics.relativity:452950 alt.astronomy:297508 Sergio wrote: > > On 3/16/2018 2:03 PM, Keith Stein wrote: > > On 16/03/2018 06:15, The Starmaker wrote: > > > >> See what they say. > > > > Let us, for the sake of argument, assume that i am on a galaxy which is > > 10,000,000,000 light years from the earth. By a bit of good > > planning i have my laser with me and i shine this laser at you for a > > whole year. The front of this laser beam will take exactly > > 10,000,000,000 to reach you here on Earth (hopefully you will still be > > alive eh!). The rear end of my laser signal will take slightly longer to > > reach you because the speed of light has decreased in the year i've been > > holding this laser. If light decreases by my suggestion of one part in > > 10 billion per year, the rear end of the signal will take exactly > > 10,000,000,001 years to reach you here on Earth. > > > > Thus the light beam from my laser is stretch by a factor of 2 ( because > > the end of the beam left 1 year after the start, and took 1 year longer > > on the journey.). However the number of waves sent will be exactly the > > same as the number received, (assuming you are careful and don't miss > > any,) so the wavelength must also have been stretched by a factor of 2. > > This is equivalent to a red-shift of 1, and corresponds reasonably well > > with what is found in practice, in our observatories. > > > > Talking Rock eh! > > if your laser has a divergance of 0.01 mrad how much path loss is > there (1/d^2) over 10,000,000,000 light years ? > > How much power output is needed at your laser to be detectable on earth > using a photomultiplier tube ? Do you have any idea how many people can get by life without ever knowing the answer to that? Have you ever seen a two headed elephant??