Thursday, December 24, 2009
Tuesday, December 15, 2009
Nuts and bolts (15/12/09)
Some interesting items I came across recently worth a look at:
Interstellar Propulsion Research: Realistic Possibilities and Idealistic Dreams by Les Johnson gives an introductory rundown on the current status of possible interstellar missions and propulsion options. Apart from the mentioned warp drive (update: read this and this), all of the options are based on sound physics however all of them have severe technical and engineering difficulties to overcome if they are going to happen one day. Ironically getting the hardware required into orbit for these big spacecraft could be the biggest hurdle to overcome as using chemical rockets is expensive. The above options are based on our current understanding of Physics and we still have a lot to learn how nature really works.
The Final Frontier: The Science of Star Trek, interview with Lawrence Krauss. I read the first version of his book years ago and found it quite stimulating reading should interest all you Star Trek fans out there. I saw the world premiere opening of the movie at the Sydney Opera House and got a few autographs myself from the (new) Spock, Sulu and JJ Abrams, I liked the movie.
A Blueprint for a Quantum Propulsion Machine, here's also a review from Paul Gilster on this paper by Alexander Feigel. It remains to be seen if these so called "magneto-electric particles" do change the momentum of the quantum vacuum and thereby provide a means to change the orientation of a spacecraft without using propellant although many do this already using gyroscopes for eg however the physics if sound would be very interesting as this would provide another avenue to study the Quantum Vacuum. Another paper on this worth reading is here.
Been busy working on Sydney Harbour most days day and night as it is the busy season here. Some recent photos: Nice sailing boat in Farm Cove and checkout this sailing boat skipper going under the Anzac bridge, got his air draft right! Big tow job Bradley's Head outbound (click on photos for larger version).
Interstellar Propulsion Research: Realistic Possibilities and Idealistic Dreams by Les Johnson gives an introductory rundown on the current status of possible interstellar missions and propulsion options. Apart from the mentioned warp drive (update: read this and this), all of the options are based on sound physics however all of them have severe technical and engineering difficulties to overcome if they are going to happen one day. Ironically getting the hardware required into orbit for these big spacecraft could be the biggest hurdle to overcome as using chemical rockets is expensive. The above options are based on our current understanding of Physics and we still have a lot to learn how nature really works.
The Final Frontier: The Science of Star Trek, interview with Lawrence Krauss. I read the first version of his book years ago and found it quite stimulating reading should interest all you Star Trek fans out there. I saw the world premiere opening of the movie at the Sydney Opera House and got a few autographs myself from the (new) Spock, Sulu and JJ Abrams, I liked the movie.
A Blueprint for a Quantum Propulsion Machine, here's also a review from Paul Gilster on this paper by Alexander Feigel. It remains to be seen if these so called "magneto-electric particles" do change the momentum of the quantum vacuum and thereby provide a means to change the orientation of a spacecraft without using propellant although many do this already using gyroscopes for eg however the physics if sound would be very interesting as this would provide another avenue to study the Quantum Vacuum. Another paper on this worth reading is here.
Been busy working on Sydney Harbour most days day and night as it is the busy season here. Some recent photos: Nice sailing boat in Farm Cove and checkout this sailing boat skipper going under the Anzac bridge, got his air draft right! Big tow job Bradley's Head outbound (click on photos for larger version).
Monday, November 30, 2009
Poem mystery author
Although I can't say I'm a big fan of poetry, I do like a very few which deal with the stars, our Universe and (big surprise here) Man's quest to venture to the stars. When I was a small boy and pointed my telescope to Saturn for the first time, this was one of those moments you never forget for the rest of your life. After countless nights behind the eyepiece (it's quite addictive!), one eventually starts to ponder on thoughts on interstellar travel and watching StarTrek makes it worse ;-) There is one poem which I can't seem to find out who wrote it. I've posted the question to poem newsgroups and contacted various knowledgeable people but to no avail. It's engraved on the back on one of my brass compasses (Dollond London) which I got from a flea market a while ago next the Maritime Museum. Do you know who wrote this poem so I can give this mystery author proper credit?
One of the reasons why I bought this compass was because I liked this poem very much, if I didn't know better my first thoughts were either a Physicist wrote it or an author with deep thoughts on Nature. It talks about time, "a continuum moves and swirls..." (the vacuum?), the celestial sphere and life. Talk about big topics! The vacuum is central to Physics and today is still "beyond my inner sight and imagination" ie Physicists still don't understand it at the quantum level although they are getting better. Actually understanding the vacuum has been central to Physics most of our history, see this very interesting painting.
Some of you who work on Sydney Harbour may have noticed that Thor Gitta was docked in White Bay for quite a while (over a month), the mystery why she was there for all this time has been solved: she was waiting for this barge to unload her big load of cable:
Some of you who work on Sydney Harbour may have noticed that Thor Gitta was docked in White Bay for quite a while (over a month), the mystery why she was there for all this time has been solved: she was waiting for this barge to unload her big load of cable:
Tuesday, November 17, 2009
Cosmology, The Big Bang and Entropy
I went to Sean Carroll's talk yesterday at Sydney University. As many of you are aware, Sean is one of the bloggers on Cosmic Variance and is touring Australia for his talks. He also has an upcoming book titled From Here to Eternity: The Quest for the Ultimate Theory of Time.
Sean talked about all the big ideas that face Cosmologists these days and in particular Entropy and its relation to the evolution of our Universe starting from a state of low entropy / high order progressing towards a state of high entropy / low order. I didn't like his interpretation of time (particularly the "arrow of time") as mentioned in my previous post and as for the state of the Universe, this is ambiguous because we cannot observe the Universe from the outside hence there is no entropy for the Universe either.
Cosmologists have a fairly good idea what the state of the Universe was 1 second after the Big Bang however at "t = 0" (time cannot be defined here as there is no matter at this stage hence no clocks), no one knows as General Relativity breaks down however before the Big Bang? Sean speculated on an idea that our Universe may have begun from a single quantum fluctuation from the inherent energy of the vacuum, ie we live in a baby Universe an offshoot from another Universe. There was quite a good turnup and the lecture theatre was pretty full, all in all enjoyed the talk.
Still experimenting with $\LaTeX$ in Blogger using this script. Testing...
\[\tan(2\theta) = {2\tan\theta \over 1-\tan^2\theta}\]
\[\int \csc^2x\, dx = -\cot x+ C.\]
\[\ P_{r-j}=\begin{cases} 0& \text{if $r-j$ is odd},\\ r!\,(-1)^{(r-j)/2}& \text{if $r-j$ is even}. \end{cases}\]
\[\qquad \lim_{\alpha\to \infty} {\sin\alpha \over \alpha} = 0\]
\[\root n \of {\prod_{i=1}^n X_i} \leq {1 \over n} \sum_{i=1}^n\]
\[\ \cfrac{1}{\sqrt{2}+\cfrac{1}{\sqrt{2}+\cfrac{1}{\sqrt{2}+\dotsb }}}\]
\[\ \nabla \cdot \mathbf{D} = \rho_f \]
\[\ \nabla \cdot \mathbf{B} = 0 \]
\[\ \nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}} {\partial t} \]
\[\ \nabla \times \mathbf{H} = \mathbf{J}_f + \frac{\partial \mathbf{D}} {\partial t } \]
\[\ \boxed{m &= \frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}}}\]
Cosmologists have a fairly good idea what the state of the Universe was 1 second after the Big Bang however at "t = 0" (time cannot be defined here as there is no matter at this stage hence no clocks), no one knows as General Relativity breaks down however before the Big Bang? Sean speculated on an idea that our Universe may have begun from a single quantum fluctuation from the inherent energy of the vacuum, ie we live in a baby Universe an offshoot from another Universe. There was quite a good turnup and the lecture theatre was pretty full, all in all enjoyed the talk.
Still experimenting with $\LaTeX$ in Blogger using this script. Testing...
\[\tan(2\theta) = {2\tan\theta \over 1-\tan^2\theta}\]
\[\int \csc^2x\, dx = -\cot x+ C.\]
\[\ P_{r-j}=\begin{cases} 0& \text{if $r-j$ is odd},\\ r!\,(-1)^{(r-j)/2}& \text{if $r-j$ is even}. \end{cases}\]
\[\qquad \lim_{\alpha\to \infty} {\sin\alpha \over \alpha} = 0\]
\[\root n \of {\prod_{i=1}^n X_i} \leq {1 \over n} \sum_{i=1}^n\]
\[\ \cfrac{1}{\sqrt{2}+\cfrac{1}{\sqrt{2}+\cfrac{1}{\sqrt{2}+\dotsb }}}\]
\[\ \nabla \cdot \mathbf{D} = \rho_f \]
\[\ \nabla \cdot \mathbf{B} = 0 \]
\[\ \nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}} {\partial t} \]
\[\ \nabla \times \mathbf{H} = \mathbf{J}_f + \frac{\partial \mathbf{D}} {\partial t } \]
\[\ \boxed{m &= \frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}}}\]
Sunday, November 15, 2009
Review: LyX and viXra
Been busy the last few days between work learning about LaTeX. Widely used by the academic and research community to write up high quality documents, scientific papers, books etc and especially useful for writting out mathematical formulae with their many special formatting requirements. The text it produces is beautiful.
I tested out LyX, which is a free Windows based Graphical User Interface (GUI) document processor for LaTeX and automatically will download MiKTeX during installation which is also required for your computer. Seems to work very well on my small laptop. Once you write up your document, you can preview it with Lyx's DVI previewer. Once you're happy with it, export the document in Adobe PDF format and you're done. LaTeX has many formatting tags if you look at the source code and although Lyx has also many GUI buttons, it's useful to sometimes type in the code by hand. There's also an excellent beginer's guide to LaTeX which I found handy called A Gentle Introduction to TEX. Great thing is, MiKTeX and LyX are both free for download! Google Documents also have the ability to insert equations and their online chart rendering feature has LaTeX command options (see links for the following):
A few days ago I also found out about the new viXra.org e-print archive. Unlike arXiv.org, this is open to anyone who wants to publish a paper and you don't need a "sponsor" (which is required by arXiv). This is great for people who aren't affililated with a research institution, university etc or can't find someone to endorse their paper. There are many Physics papers out there that are highly speculative and many academics aren't willing to be affiliated with a paper that at first appearances could be junk. The only problem is this doesn't help scientific progress. Their Why page explains all this in more detail. Because this is open to anyone, many junk papers will be found there however there are some interesting ones as well worth a read, all in all think viXra is a great idea. Worth keeping an eye on.
Attached photos: Students practicing survival at sea skills, liferaft deployment etc at the Qantas training pool, Sydney Airport.
I tested out LyX, which is a free Windows based Graphical User Interface (GUI) document processor for LaTeX and automatically will download MiKTeX during installation which is also required for your computer. Seems to work very well on my small laptop. Once you write up your document, you can preview it with Lyx's DVI previewer. Once you're happy with it, export the document in Adobe PDF format and you're done. LaTeX has many formatting tags if you look at the source code and although Lyx has also many GUI buttons, it's useful to sometimes type in the code by hand. There's also an excellent beginer's guide to LaTeX which I found handy called A Gentle Introduction to TEX. Great thing is, MiKTeX and LyX are both free for download! Google Documents also have the ability to insert equations and their online chart rendering feature has LaTeX command options (see links for the following):
Attached photos: Students practicing survival at sea skills, liferaft deployment etc at the Qantas training pool, Sydney Airport.
Wednesday, November 4, 2009
What exactly is time?
I came across today the following paper reviewed on the arXiv Blog and also on arXiv: Can the Arrow of Time be understood from Quantum Cosmology?
The question itself used as the title is flawed. There is no such thing as the "Arrow of Time" in Nature and after reading the paper suspect this will lead to another Not Even Wrong theory. This is a common misunderstanding in Physics so what exactly is time? It's about time we have a look. There's a wiki article however I prefer the explanation on p40 of the first volume of Motion Mountain:
Schiller goes on:
"Time is a concept introduced specially to describe the flow of events around us; it does not itself flow, it describes flow. Time does not advance. Time is neither linear nor cyclic. The idea that time flows is as hindering to understanding nature as is the idea that mirrors Page 71 exchange right and left. The misleading use of the expression ‘flow of time’, propagated first by some flawed Ref. 36 Greek thinkers and then again by Newton, continues. Aristotle (384/3–322 bce), careful to think logically, pointed out its misconception, and many did so after him. Nevertheless, expressions such as ‘time reversal’, the ‘irreversibility of time’, and the much-abused ‘time’s arrow’ are still common. Just read a popular science magazine chosen at random.
The fact is: time cannot be reversed, only motion can, or more precisely, only velocities of objects; time has no arrow, only motion has; it is not the flow of time that humans are unable to stop, but the motion of all the objects in nature. Incredibly, there are even books written by respected physicists that study different types of ‘time’s arrows’ and compare them with each other. Predictably, no tangible or new result is extracted. Time does not flow."
There you have it, if you were thinking of becoming a time traveller with exotic machinery don't waste your time. However time machines are available for purchase if you want one ;-), they only allow you to see back in time though and we are constrained to seeing the observable Universe.
Because light from the Sun for eg takes just over 8 minutes to reach us here on Earth, astronomical objects you see in the sky are essentially as they were when the light left them and because of the vastness of space and the speed of light, it takes time for the light from these objects to reach us. For eg light from our neighbour the Andromeda Galaxy takes 2.5 million years to reach us so if you look at it with a telescope (or with binoculars), you are seeing the galaxy as it was 2.5 million years ago. The bigger the telescope, the further you can see back:
The question itself used as the title is flawed. There is no such thing as the "Arrow of Time" in Nature and after reading the paper suspect this will lead to another Not Even Wrong theory. This is a common misunderstanding in Physics so what exactly is time? It's about time we have a look. There's a wiki article however I prefer the explanation on p40 of the first volume of Motion Mountain:
"Time is what we read from a clock."That's it! Your first intuition is correct ie you check your clock to find out what time it is. Note that clocks can be the Moon, the Sun, sundials, atomic clocks, Harrison's H1 clock etc.
Schiller goes on:
"Time is a concept introduced specially to describe the flow of events around us; it does not itself flow, it describes flow. Time does not advance. Time is neither linear nor cyclic. The idea that time flows is as hindering to understanding nature as is the idea that mirrors Page 71 exchange right and left. The misleading use of the expression ‘flow of time’, propagated first by some flawed Ref. 36 Greek thinkers and then again by Newton, continues. Aristotle (384/3–322 bce), careful to think logically, pointed out its misconception, and many did so after him. Nevertheless, expressions such as ‘time reversal’, the ‘irreversibility of time’, and the much-abused ‘time’s arrow’ are still common. Just read a popular science magazine chosen at random.
The fact is: time cannot be reversed, only motion can, or more precisely, only velocities of objects; time has no arrow, only motion has; it is not the flow of time that humans are unable to stop, but the motion of all the objects in nature. Incredibly, there are even books written by respected physicists that study different types of ‘time’s arrows’ and compare them with each other. Predictably, no tangible or new result is extracted. Time does not flow."
There you have it, if you were thinking of becoming a time traveller with exotic machinery don't waste your time. However time machines are available for purchase if you want one ;-), they only allow you to see back in time though and we are constrained to seeing the observable Universe.
Because light from the Sun for eg takes just over 8 minutes to reach us here on Earth, astronomical objects you see in the sky are essentially as they were when the light left them and because of the vastness of space and the speed of light, it takes time for the light from these objects to reach us. For eg light from our neighbour the Andromeda Galaxy takes 2.5 million years to reach us so if you look at it with a telescope (or with binoculars), you are seeing the galaxy as it was 2.5 million years ago. The bigger the telescope, the further you can see back:
At time t = 0, current Physics cannot explain what happened as the Physics cube mentioned in the previous post isn't complete. And before that? Roger Penrose gave a good talk in 2007 at Darling Harbour titled: What happened before the Big Bang?
Photos: Claudia I coming into Blackwattle Bay the other day delivering more concrete supplies.
Thursday, October 29, 2009
Propulsion Physics and the future ahead
I recently stumbled on a 2004 presentation by Marc Millis while doing some searches and is well put together. Unfortunetly NASA's former Breakthrough Propulsion Physics (BPP) Project (wiki article here) funding got cancelled a few years ago and today I read in Paul Gilster's Centauri Dreams outlining a report which recommends that NASA reinstate the (also cancelled!) NASA Institute for Advanced Concepts in one form or another, no doubt there are many reasons why they both got cancelled (which I think cancelling BPP was a big mistake regardless of NASA's new lunar or otherwise objectives considering the already minimal funding it received and the great job Marc and others put into it) however unfortunetly this means today that there are no substantially funded organisations dedicated to organising and researching advanced concepts or potential physics breakthroughs that could lead to making interstellar travel practical, economical and a viable proposition so we wait and see what mainstream Physics and individual researchers come up next.
Last night I watched the awesome Ares I-X launch and this is only the little puppy version of the big one they'll be using to launch crew to the Moon (however I'm reading in today's paper that the Moon program funding, yes you guessed could be cancelled!). No doubt money's tight for everyone at the moment but when I see how public money is wasted these days on other things with questional benefits to the public, I wonder...
I've outlined in a previous post why it is important for humans to settle on another planet (preferably on another Earth-like planet which means an interstellar journey to other star systems) and rockets just won't do the job (and are expensive, the Ares launch cost $445m according to the today's paper article).
So it's back to Propulsion Physics and first principles (or revised first principles?). There's no need for me to reiterate on Marc's presentation but the most important points are on p8 and p34:
Top right corner specifically. This is good as a Relativistic Quantum Theory of Gravity could lead to BPP and answer many unknowns in Physics and the Universe. However only seeking a unified theory of Physics isn't a good approach in my view. String Theorists have spent the last 25 years searching for their unified theory with so far a dead end (Peter Woit's book Not Even Wrong is a good read on this) and makes no new predictions in Physics that are verifiable and testable with the Large Hadron Collider. Even Einstein in his later years searched a unified theory of Physics to no avail. As pointed out earlier the Propulsion focus shouldn't be left out in the mainstream Physics research community. I'm not saying that all research into String Theories for eg should be abandoned (although myself I think it's a dead end) however there needs to be a more balanced focus to propulsion in mainstream Physics research, sometimes approaching a problem from a different angle can lead to productive results and in my view this is why cancelling the BPP Program at NASA was a huge mistake (where they should be leading the world by example). Practical and economical Interstellar flight may turn out to be impossible however while seeking solutions (as history shows in Physics) sometimes people stumble on other unexpected Physics.
What is the current state of affairs? As the BPP site mentions, "No breakthroughs appear imminent." There are many theories floating around however, either the theories haven't stood up to experiment or are inconclusive or there is no funding to test the theories put forth. Out of all the "crackpot theories" submitted each year, if one turns out to be correct, then this could change everything. There needs to be a funded program (like the BPP Project) that investigates and manages all this. For those who wish to dig deeper into all this a very good starting point is the following book: Frontiers of Propulsion Science. For those wondering checkout: What would a relativistic interstellar traveller see? I'll finish this post with a paragraph I like by Walter Drösher and Jochem Hauser in their paper (although I got a bit lost in their Extended Heim Theory and don't quite understand it):
Last night I watched the awesome Ares I-X launch and this is only the little puppy version of the big one they'll be using to launch crew to the Moon (however I'm reading in today's paper that the Moon program funding, yes you guessed could be cancelled!). No doubt money's tight for everyone at the moment but when I see how public money is wasted these days on other things with questional benefits to the public, I wonder...
I've outlined in a previous post why it is important for humans to settle on another planet (preferably on another Earth-like planet which means an interstellar journey to other star systems) and rockets just won't do the job (and are expensive, the Ares launch cost $445m according to the today's paper article).
So it's back to Propulsion Physics and first principles (or revised first principles?). There's no need for me to reiterate on Marc's presentation but the most important points are on p8 and p34:
- Mass: Discover new propulsion methods that eliminate (or dramatically reduce) the need for propellant.
- Speed: Discover how to circumvent existing limits (light-speed) to dramatically reduce transit times.
- Energy: Discover new energy methods to power these propulsion devices.
"These goals are THE breakthroughs needed to conquer the presently impossible ambition of human interstellar exploration."I'll talk about the Physics of these 3 points in a future post, what striked me in this presentation and what I wanted to mention in this post was on the last page:
"Science community does not address propulsion opportunities, but instead seeks a Theory of Everything. A propulsion focus increases options."This is a good point, rephrased the Science community seeks to complete the Physics cube below:
Top right corner specifically. This is good as a Relativistic Quantum Theory of Gravity could lead to BPP and answer many unknowns in Physics and the Universe. However only seeking a unified theory of Physics isn't a good approach in my view. String Theorists have spent the last 25 years searching for their unified theory with so far a dead end (Peter Woit's book Not Even Wrong is a good read on this) and makes no new predictions in Physics that are verifiable and testable with the Large Hadron Collider. Even Einstein in his later years searched a unified theory of Physics to no avail. As pointed out earlier the Propulsion focus shouldn't be left out in the mainstream Physics research community. I'm not saying that all research into String Theories for eg should be abandoned (although myself I think it's a dead end) however there needs to be a more balanced focus to propulsion in mainstream Physics research, sometimes approaching a problem from a different angle can lead to productive results and in my view this is why cancelling the BPP Program at NASA was a huge mistake (where they should be leading the world by example). Practical and economical Interstellar flight may turn out to be impossible however while seeking solutions (as history shows in Physics) sometimes people stumble on other unexpected Physics.
What is the current state of affairs? As the BPP site mentions, "No breakthroughs appear imminent." There are many theories floating around however, either the theories haven't stood up to experiment or are inconclusive or there is no funding to test the theories put forth. Out of all the "crackpot theories" submitted each year, if one turns out to be correct, then this could change everything. There needs to be a funded program (like the BPP Project) that investigates and manages all this. For those who wish to dig deeper into all this a very good starting point is the following book: Frontiers of Propulsion Science. For those wondering checkout: What would a relativistic interstellar traveller see? I'll finish this post with a paragraph I like by Walter Drösher and Jochem Hauser in their paper (although I got a bit lost in their Extended Heim Theory and don't quite understand it):
Wednesday, October 28, 2009
What cats talk about at the Fish Markets
There are quite a lot of cats at the wharf where the boats are kept and wondered what they sometimes talk about, now I know! :-))
Tuesday, October 27, 2009
Who said the sky's the limit and is Physics wrong?
(23/10/09)
I was walking in the city earlier today and saw these ad billboards in the street:
Normally I wouldn't take a second look (I don't even have a credit card myself, think they're a waste of money) but saw a rocket in the stars so had to study it in detail! :-)) These ads actually give sound advice for anyone into Physics&Astronomy! When I looked at the first ad "Who said the sky's the limit?", immediate thoughts were, well Nature says what the limits are and the maximum speed that anything can travel in our Universe is the speed of light, C = 300,000Km/s.This applies not only to light but also matter, radio waves, information transfer etc. Protons, electrons etc are routinely accelerated to 0.99C at particle accelerators but never go over the speed limit.
Einstein's Special Theory of Relativity 101: "The speed of light in vacuum is always C, independent of the motion of thesource or of the observer".
This at first seems counter intuitive after all if you see a car moving at 100Km/h on the freeway then light leaving their headlights should be travelling at 100Km/h + C right? Wrong, light still travels at C! (Don't worry about the air makes very little difference you could do this in space for eg). This makes perfect sense if you think of everything you see around you immersed in the vacuum and this vacuum (which is a complicated "quantum fluctuating soup") doesn't allow light to travel faster then C. Strange things happen as you travel 1/3C or faster (time dilation etc...)
Second ad basically was telling me that although exploring the Universe with telescopes etc is good, get off your butts and build some ships to do some serious exploring beyond the solar system! ;-) Given the distances involved in our Galaxy, the speed limit (C) imposed on us by the vacuum is problematic. Closest star is 4.2 lightyears away for eg however if you're planning your next trip to Alpha Centauri don't despair this isn't the end of the story there are different types of vacuums which are under study... even Roger Penrose (who wrote the masterpiece The Road to Reality) recently mentions that our current theories are "wrong" although some don't agree with all he says it's interesting reading:
http://discovermagazine.com/2009/sep/06-discover-interview-roger-penrose-says-physics-is-wrong-string-theory-quantum-mechanics
Looking forward to some more American Express credit card ads! ;-)
I was walking in the city earlier today and saw these ad billboards in the street:
Normally I wouldn't take a second look (I don't even have a credit card myself, think they're a waste of money) but saw a rocket in the stars so had to study it in detail! :-)) These ads actually give sound advice for anyone into Physics&Astronomy! When I looked at the first ad "Who said the sky's the limit?", immediate thoughts were, well Nature says what the limits are and the maximum speed that anything can travel in our Universe is the speed of light, C = 300,000Km/s.This applies not only to light but also matter, radio waves, information transfer etc. Protons, electrons etc are routinely accelerated to 0.99C at particle accelerators but never go over the speed limit.
Einstein's Special Theory of Relativity 101: "The speed of light in vacuum is always C, independent of the motion of thesource or of the observer".
This at first seems counter intuitive after all if you see a car moving at 100Km/h on the freeway then light leaving their headlights should be travelling at 100Km/h + C right? Wrong, light still travels at C! (Don't worry about the air makes very little difference you could do this in space for eg). This makes perfect sense if you think of everything you see around you immersed in the vacuum and this vacuum (which is a complicated "quantum fluctuating soup") doesn't allow light to travel faster then C. Strange things happen as you travel 1/3C or faster (time dilation etc...)
Second ad basically was telling me that although exploring the Universe with telescopes etc is good, get off your butts and build some ships to do some serious exploring beyond the solar system! ;-) Given the distances involved in our Galaxy, the speed limit (C) imposed on us by the vacuum is problematic. Closest star is 4.2 lightyears away for eg however if you're planning your next trip to Alpha Centauri don't despair this isn't the end of the story there are different types of vacuums which are under study... even Roger Penrose (who wrote the masterpiece The Road to Reality) recently mentions that our current theories are "wrong" although some don't agree with all he says it's interesting reading:
http://discovermagazine.com/2009/sep/06-discover-interview-roger-penrose-says-physics-is-wrong-string-theory-quantum-mechanics
Looking forward to some more American Express credit card ads! ;-)
50 years of space exploration map
(17/10/09)
Checkout this beautiful map illustrating where our probes have been so far in the solar system:
http://wanderingspace.net/2009/10/50-years-of-space-exploration-map/
There's a zoomable version at:
http://books.nationalgeographic.com/map/map-day/2008/09/18
Very nice. Checkout the scale at the bottom, you'll see Voyager 1 at 10 billion miles (16.5 billion Kms) way past Pluto's orbit heading into interstellar space and this is the first human made object to leave the solar system. It was launched in 1977 and is still transmitting! No batteries onboard, the probe is powered by Radioisotope Thermoelectric Generators (RTGs):
http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator
which should generate electricity for the probe till 2025, at this distance from the sun, solar panels don't work. I think if ET finds the onboard golden record they should have a box office sellout at the movies on their planet! ;-)
Attached photo: Suncat getting ready for the Manly fast ferry service.
Checkout this beautiful map illustrating where our probes have been so far in the solar system:
http://wanderingspace.net/2009/10/50-years-of-space-exploration-map/
There's a zoomable version at:
http://books.nationalgeographic.com/map/map-day/2008/09/18
Very nice. Checkout the scale at the bottom, you'll see Voyager 1 at 10 billion miles (16.5 billion Kms) way past Pluto's orbit heading into interstellar space and this is the first human made object to leave the solar system. It was launched in 1977 and is still transmitting! No batteries onboard, the probe is powered by Radioisotope Thermoelectric Generators (RTGs):
http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator
which should generate electricity for the probe till 2025, at this distance from the sun, solar panels don't work. I think if ET finds the onboard golden record they should have a box office sellout at the movies on their planet! ;-)
Attached photo: Suncat getting ready for the Manly fast ferry service.
Greenwich Longitude turns 125 years old!
(14/10/09)
The Prime Meridian (Longitude 0°) at Greenwich Observatory turned 125 years old! It was born on the 13th October 1884, read about it at:
http://backreaction.blogspot.com/2009/10/125-years-of-greenwich-longitude.html
The Prime Meridian (Longitude 0°) at Greenwich Observatory turned 125 years old! It was born on the 13th October 1884, read about it at:
http://backreaction.blogspot.com/2009/10/125-years-of-greenwich-longitude.html
Gigagalaxy Zoom project
(12/10/09)
Here's a useful website if you haven't got the time to do some stargazing or just wondered what's at the centre of our galaxy, checkout the recently released:
http://www.gigagalaxyzoom.org/
Has high quality photos of our stellar neighbourhoods and you can zoom in and out from some photos etc. If you don't have the time to visit the centre of our galaxy, here it is:
http://www.eso.org/gallery/v/ESOPIA/Quasars/phot-46-08-fullres.tif.html
Don't get too close though, there's a black hole at the centre ;-)
Attached photo: Steve Irwin leaving Sydney today http://www.seashepherd.org/
Here's a useful website if you haven't got the time to do some stargazing or just wondered what's at the centre of our galaxy, checkout the recently released:
http://www.gigagalaxyzoom.org/
Has high quality photos of our stellar neighbourhoods and you can zoom in and out from some photos etc. If you don't have the time to visit the centre of our galaxy, here it is:
http://www.eso.org/gallery/v/ESOPIA/Quasars/phot-46-08-fullres.tif.html
Don't get too close though, there's a black hole at the centre ;-)
Attached photo: Steve Irwin leaving Sydney today http://www.seashepherd.org/
Submarine neutrino communication
(07/10/09)
Here's some interesting reading for you submarine buffs out there:
http://www.technologyreview.com/blog/arxiv/24203/
This Physicist published a paper on how to use neutrinos as a possible effective communication method for submarines underwater to receive messages only. As you know only extra low frequency (ELF-VLF) radio waves can be used for communications by submarines underwater as the higher frequencies get severely attenuated and because of the very low frequency, only very low bit rates can be used. Neutrinos are particles that are created in certain nuclear reactions and radioactive decays, they travel close to the speed of light and interact very rarely with normal matter. Although we don't realise it, right now your body is emitting roughly 400 neutrinos per second due to the naturally occuring radioactive isotopes of Calcium and Potassium in your bones. You are basically neutrino transmitters.
Attached photos:
- Someone who named this barge "Nebula" must be into Astronomy ;-)
- This catamaran had a Compass Adjuster onboard the other morning, heard them call up Harbour Control on Ch13 when they were using transits in the channel. I better finish the course ASAP!
Here's some interesting reading for you submarine buffs out there:
http://www.technologyreview.com/blog/arxiv/24203/
This Physicist published a paper on how to use neutrinos as a possible effective communication method for submarines underwater to receive messages only. As you know only extra low frequency (ELF-VLF) radio waves can be used for communications by submarines underwater as the higher frequencies get severely attenuated and because of the very low frequency, only very low bit rates can be used. Neutrinos are particles that are created in certain nuclear reactions and radioactive decays, they travel close to the speed of light and interact very rarely with normal matter. Although we don't realise it, right now your body is emitting roughly 400 neutrinos per second due to the naturally occuring radioactive isotopes of Calcium and Potassium in your bones. You are basically neutrino transmitters.
Attached photos:
- Someone who named this barge "Nebula" must be into Astronomy ;-)
- This catamaran had a Compass Adjuster onboard the other morning, heard them call up Harbour Control on Ch13 when they were using transits in the channel. I better finish the course ASAP!
Monday, October 26, 2009
Saturn at equinox and the same colour illusion
(04/10/09)
Checkout these interesting Astronomy Picture of the Day photos:
http://antwrp.gsfc.nasa.gov/apod/ap090930.html
http://antwrp.gsfc.nasa.gov/apod/ap091004.html
Goes to show when it comes to Science, appearances can be deceiving, don't always trust your brain ;-) Attached photos: Lithgow today under Anzac bridge (with a nice new Rosman Ferries paint job) and tugboats busy with CSL Pacific a few days ago 6am in White Bay, now this ship definately needs a paint job.
Checkout these interesting Astronomy Picture of the Day photos:
http://antwrp.gsfc.nasa.gov/apod/ap090930.html
http://antwrp.gsfc.nasa.gov/apod/ap091004.html
Goes to show when it comes to Science, appearances can be deceiving, don't always trust your brain ;-) Attached photos: Lithgow today under Anzac bridge (with a nice new Rosman Ferries paint job) and tugboats busy with CSL Pacific a few days ago 6am in White Bay, now this ship definately needs a paint job.
Internal Combustion Engines MIT OpenCourseWare now online
(24/09/09)
For those interested, MIT has released today free online course notes for internal combustion engines including diesel engines:
http://ocw.mit.edu/OcwWeb/Mechanical-Engineering/2-61Spring-2008/CourseHome/
Click on "Lectures notes" on the sidebar to donwload individual lecture notes or you can download the lot. Last lecture explains hydrogen fuel cells and other techonlogies. Attached today's harbour photos.
For those interested, MIT has released today free online course notes for internal combustion engines including diesel engines:
http://ocw.mit.edu/OcwWeb/Mechanical-Engineering/2-61Spring-2008/CourseHome/
Click on "Lectures notes" on the sidebar to donwload individual lecture notes or you can download the lot. Last lecture explains hydrogen fuel cells and other techonlogies. Attached today's harbour photos.
New rocky exoplanet found and first detailed photos of an atom!
(18/09/09)
Lots of good things happening in Physics & Astronomy this week! I read an article in today's MX newspaper but check the articles below for more info:
http://www.eso.org/public/outreach/press-rel/pr-2009/pr-33-09.html
http://www.centauri-dreams.org/?p=9451
The Astronomers did a good job and confirmed that a planet outside our solar system (500 lightyears away) is rocky (not like Jupiter size planets for eg made of gas). Might be a bit too hot for your comfort though so lets hope the Astronomers get lucky and find another Earth-like planet soon because this one is starting to get too crowded ;-) Have a look at these first detailed photos of the electron clouds of carbon atoms:
http://www.insidescience.org/research/first_detailed_photos_of_atoms
The nucleus itself (protons and neutrons) is too small to be seen, between the electrons and the nucleaus itself it's empty space.
Attached photos: ships docked in White Bay last Saturday night. Reef Endeavour has been there for months and Golden Mermaid with the red flashing light on top stank like fertiliser or nitrates, busy discharging into lots of tankers waiting at the wharf.
Lots of good things happening in Physics & Astronomy this week! I read an article in today's MX newspaper but check the articles below for more info:
http://www.eso.org/public/outreach/press-rel/pr-2009/pr-33-09.html
http://www.centauri-dreams.org/?p=9451
The Astronomers did a good job and confirmed that a planet outside our solar system (500 lightyears away) is rocky (not like Jupiter size planets for eg made of gas). Might be a bit too hot for your comfort though so lets hope the Astronomers get lucky and find another Earth-like planet soon because this one is starting to get too crowded ;-) Have a look at these first detailed photos of the electron clouds of carbon atoms:
http://www.insidescience.org/research/first_detailed_photos_of_atoms
The nucleus itself (protons and neutrons) is too small to be seen, between the electrons and the nucleaus itself it's empty space.
Attached photos: ships docked in White Bay last Saturday night. Reef Endeavour has been there for months and Golden Mermaid with the red flashing light on top stank like fertiliser or nitrates, busy discharging into lots of tankers waiting at the wharf.
Lucas Heights nuclear reactor open day
(13/09/09)
In case you didn't know the Lucas Heights nuclear reactor is having an open day for the public on Saturday 19th September (thanks to Tony for the info):
http://www.ansto.gov.au/
Not sure if I can make it that day but if I'm free I'll be bringingwith me my specially modified geiger counter
:-) I checked again tonight (Sunday) how many ships there are anchored off Newcastle on http://marinetraffic.com/ and I counted over 40 ships!!!?! Talk about busy little Harbour!
In case you didn't know the Lucas Heights nuclear reactor is having an open day for the public on Saturday 19th September (thanks to Tony for the info):
http://www.ansto.gov.au/
Not sure if I can make it that day but if I'm free I'll be bringingwith me my specially modified geiger counter
:-) I checked again tonight (Sunday) how many ships there are anchored off Newcastle on http://marinetraffic.com/ and I counted over 40 ships!!!?! Talk about busy little Harbour!
Live Ships AIS Map online
(10/09/09)
Checkout this website:
http://marinetraffic.com/
Shows on the map live AIS information of vessels around the world including Sydney. Checkout how many ships there are outside Newcastle waiting for coal!! You'll see some of the Sydney Ferries for eg also have AIS and you can click on the icons to get a photo of the boat and other info if available. Attached photos: Cronulla Ferries.
Checkout this website:
http://marinetraffic.com/
Shows on the map live AIS information of vessels around the world including Sydney. Checkout how many ships there are outside Newcastle waiting for coal!! You'll see some of the Sydney Ferries for eg also have AIS and you can click on the icons to get a photo of the boat and other info if available. Attached photos: Cronulla Ferries.
Degaussing range and nuclear powered ships
(07/09/09)
For those who have to sometimes give commentary during the cruise, here's your big chance to impress your passengers by telling them about the degaussing range at Steele Point, Rose Bay where you sometimes see Navy ships hanging around, find out what's going on:
http://www.brighthub.com/engineering/marine/articles/43712.aspx
http://www.brighthub.com/engineering/marine/articles/43714.aspx
Another interesting article on nuclear powered ships:
http://www.brighthub.com/engineering/marine/articles/26364.aspx
If the hydrogen fuel cell water taxi doesn't kick off at least there's the nuclear powered water taxi option ;-)
For those who have to sometimes give commentary during the cruise, here's your big chance to impress your passengers by telling them about the degaussing range at Steele Point, Rose Bay where you sometimes see Navy ships hanging around, find out what's going on:
http://www.brighthub.com/engineering/marine/articles/43712.aspx
http://www.brighthub.com/engineering/marine/articles/43714.aspx
Another interesting article on nuclear powered ships:
http://www.brighthub.com/engineering/marine/articles/26364.aspx
If the hydrogen fuel cell water taxi doesn't kick off at least there's the nuclear powered water taxi option ;-)
Learning resource for Marine Engineers
(04/09/09)
Anyone studying marine engineering subjects might find this website useful:
http://www.marinediesels.info/
Although it's geared towards the big ship engines, it has lots of relevant info for smaller ones and associated machinery with neat diagrams/animations.
Anyone studying marine engineering subjects might find this website useful:
http://www.marinediesels.info/
Although it's geared towards the big ship engines, it has lots of relevant info for smaller ones and associated machinery with neat diagrams/animations.
First Hydrogen Fuel Cell Water Taxi
(03/09/09)
A few months ago you read about the first hydrogen fuel cell commercial charter boat and aircraft in Germany, here's the first water taxi launched in 2003 using this technology:
http://www.marinelog.com/DOCS/NEWSMMIII/MMIIIOct16d.html
Build some nuclear/solar/wind/ocean current power stations to make lots of electricity (these don't pump CO2 into the atmosphere) in order make hydrogen gas from sea water, hydrogen gas filling stations and you have a true zero emission transport system. Another option looked at is an engine that burns hydrogen gas(highly flammable) in a combustion chamber directly rather than using fuel cells to make electricity which drive electric motors:
http://www.atzonline.com/index.php;do=show/site=a4e/sid=5666422124a9fbc2f268fd257932636/alloc=1/id=9413
Photos attached: lifeboat drill today at the maritime museum. Note the plaque has a small typo, should read 21.2KW
A few months ago you read about the first hydrogen fuel cell commercial charter boat and aircraft in Germany, here's the first water taxi launched in 2003 using this technology:
http://www.marinelog.com/DOCS/NEWSMMIII/MMIIIOct16d.html
Build some nuclear/solar/wind/ocean current power stations to make lots of electricity (these don't pump CO2 into the atmosphere) in order make hydrogen gas from sea water, hydrogen gas filling stations and you have a true zero emission transport system. Another option looked at is an engine that burns hydrogen gas(highly flammable) in a combustion chamber directly rather than using fuel cells to make electricity which drive electric motors:
http://www.atzonline.com/index.php;do=show/site=a4e/sid=5666422124a9fbc2f268fd257932636/alloc=1/id=9413
Photos attached: lifeboat drill today at the maritime museum. Note the plaque has a small typo, should read 21.2KW
How many barges can you tow at once?
(01/09/09)
Checkout these interesting articles:
http://cargolaw.com/2009nightmare_margaret.html
Talk about heavy duty tow job, can you count how many barges they are towing?!?!! And photos about a collision between two ships M/V Marti Princess & M/V Renate Schulte June 2009:
http://cargolaw.com/2000nightmare_singles.only.html
Checkout these interesting articles:
http://cargolaw.com/2009nightmare_margaret.html
Talk about heavy duty tow job, can you count how many barges they are towing?!?!! And photos about a collision between two ships M/V Marti Princess & M/V Renate Schulte June 2009:
http://cargolaw.com/2000nightmare_singles.only.html
Onboard the Columbian Navy training ship ARC Gloria
(30/08/09)
If you haven't heard the Gloria is in Sydney for another 4 days and is docked in Circular Quay, she's
open to the public (free entry) and went onboard today, unfortunetly I couldn't sneek in the engine room
to take some more photos because of tight security but here are some to clog up your mailbox ;-)
If you haven't heard the Gloria is in Sydney for another 4 days and is docked in Circular Quay, she's
open to the public (free entry) and went onboard today, unfortunetly I couldn't sneek in the engine room
to take some more photos because of tight security but here are some to clog up your mailbox ;-)
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