113,877 reputation
5176303
bio website ratsauce.co.uk
location Chester, United Kingdom
age 53
visits member for 3 years, 10 months
seen 2 hours ago

Semi retired old time computer nerd who started programming on a Commodore Pet.

Since I'm also active in the Physics forum I should add that I started as a theoretical chemist, moved into solid state photochemistry and finally worked in industry as a colloid scientist. I only became a full time computer nerd in 1997.


Nov
17
comment How many grams of anthracite coal is needed to convert to steam?
@AlmondBaby: $L$ is the latent heat of the water i.e. it is the heat required to convert 1kg of water at 100°C to 1kg of steam at 100°C.
Nov
17
comment Time Dilation Experiment
See also Where are the time dilatational effects of orbital motion and gravitational acceleration equal?
Nov
17
comment Why isn't our universe symmetric?
@asperanz: oops, yes. Thanks :-)
Nov
17
comment Why isn't our universe symmetric?
@zibadawatimmy: see this Wikipedia page in the Low multipoles and other anomalies section. There may be anomalies in the CMB on such a large scale that they threaten the concept of large scale homogeneity. However I must stress that this is still very much an open question.
Nov
15
comment Effect of Earth's rotation on apparent weight (acceleration due to gravity)
possible duplicate of how apparent weight varies due to the rotational motion of earth
Nov
15
comment What happens to the energy of photons when two light waves with plane wavefront interferes destructively?
See also Where does energy go in destructive interference?
Nov
15
comment why a engine convert all of its heat into work?
possible duplicate of Energy density and Carnot cycle
Nov
14
comment Direction of gravitational field in Hemisphere
You're assuming that the direction of the gravitational acceleration always points towards the centre of mass, and in general this is not true.
Nov
14
comment What is the smallest length scale ever measured?
@BrandonEnright: that's why I included the weasel words directly measured. I think that the IceCube measurements are really an indirect measurement. There are all sorts of indirect measurements because energies higer than 1TeV may have to be included when calculating scattering cross sections i.e. very high energy physics will affect probabilities at lower (observable) energies. As a result arguably we have probed energies far higher than 1TeV.
Nov
14
comment Is it really possible to create some mass only from equivalent energy?
Likewise in beta decay neutrons turn into lighter particles and the missing mass turns into kinetic energy. The key thing to understand about all this is that matter is an excitation in a quantum field, as I discuss in the linked question. However I concede that the linked question doesn't directly answer what you've asked here.
Nov
14
comment Is it really possible to create some mass only from equivalent energy?
The point is that whenever any two particles collide some of their kinetic energy may be used to produce excitations in quantum fields i.e. matter. For example when you collide two protons, weighing about a GeV each, in the LHC the collision can create a Higgs boson weighing 125GeV. The extra 123GeV of mass came from the kinetic energy of the colliding protons (well, quarks).
Nov
14
comment Is a Thomson's lamp physically realistic?
This question appears to be off-topic because it is about philosophy not physics.
Nov
14
comment How to describe arbitrary accelerations in special relativity
Apologies to everyone for being a bit slow replying to your posts. Thanks to everyone who answered. Ben's method, with clarifications provided by Pulsar (I wish I could accept both) looks the most user friendly route. @user12262: thanks. I'm going to have to go through your answer very thoroughly as it's a bit over my head.
Nov
14
comment Is it really possible to create some mass only from equivalent energy?
Rajesh, the duplicate I've suggested is actually asking about matter turning into energy, rather than energy turning into matter, but it's the same physics and it does mention how energy is coverted to particles in the LHC.
Nov
14
comment Would a wormhole be able to move?
@VanCoding: if this is something you're interested in I have written several answers to questions on wormholes, most on a reasonably accessible level.
Nov
14
comment Would a wormhole be able to move?
@VanCoding: I've extended my answer to respond to your comment
Nov
14
comment If Julian Barbour is Correct, is the Speed of Light Special?
Related, though not a duplicate: What is so special about speed of light?
Nov
14
comment How to identify a “measuring rod”, and how to compare separated “measuring rods” with each other?
@user12262: OK, thanks, I think that's a fair criticism and I may have gone too far in trying to keep my answer simple. I'll have a read through it and see if i can clarify it a bit.
Nov
14
comment Direction of formation of Black Hole
@JamalS: Yes, OK, but the embedding in a higher dimension is a mathematical trick and not intended to represent anything physical. I feel this is a dangerous direction in which to lead beginners to GR :-)
Nov
14
comment Why does my measured I-V curve for a film of aluminum suggest high resistance?
Maybe you had a high contact resistance. There's no way to tell.