Fermi National Laboratory


Questions and Answers from Virtual Ask-a-Scientist of May 6, 2003

More information about the program

Moderator
Welcome to Virtual Ask-a-Scientist. I am Elizabeth Clements, of the Office of Public Affairs at Fermilab, and I will be your moderator for the evening. Our guest scientists tonight are Bruce Baller, of Fermilabís MINOS experiment and Chris White, also of Fermilabís MINOS experiment. And now we are ready for your questions.

Moderator
Learn about neutrino physics at Fermilab: http://www.fnal.gov/pub/inquiring/physics/neutrino/index.html

Moderator
Discoveries at Fermilab: The Tau Neutrino http://www.fnal.gov/pub/inquiring/physics/neutrino/discovery/index.html

Shabooty17
So what is this all about?

Chris White
You ask questions about science and we try to answer them!

Moderator
The Story of the Neutrino: http://www.fnal.gov/pub/inquiring/physics/neutrino/discovery/neutrino_story.html

Moderator
Learn more about the MINOS experiment: http://www-numi.fnal.gov/

Moderator
The MINOS Experiment Ė Main Injector Neutrino Oscillation Search http://www-numi.fnal.gov/public/minosexperiment.html

Tiny
I don't want to ask questions that you've already heard before.

Chris White
I haven't heard any yet... ask away!!

Cinder
What is the MINOS experiment all about?

Bruce Baller
The experiment is designed to look for neutrino oscillations, -> where neutrinos produced at one location change their type before they are detected somewhere else. I should have added that "oscillations" mean that they change back to their original type some time later.

Shabooty17
I am a student at Warwick high school in Virginia. My assignment was to check this site out.

Bruce Baller
Welcome. Do you have a question? I am all ears...

Moderator
The MINOS Experiment Ė Main Injector Neutrino Oscillation Search: http://www-numi.fnal.gov/public/minosexperiment.html

Rondo
Hi. How did you decide to be physicists?

Chris White
I don't know for sure... I've always wanted to know how things work, fundementally speaking.

Moderator
Questions and Answers from the Virtual Ask-a-Scientist of March 12, 2003 http://www.fnal.gov/pub/inquiring//virtual/aas_transcript3-12-03.html

Tiny What would be the reasons of an experiment like MINOS?

Bruce Baller
The standard model that we physicists all know and love doesn't allow this to happen. Neutrinos have something called a lepton number which is thought to be a conserved quantity like mass or charge. When neutrinos oscillate, they change their lepton number.

Moderator
Just what are neutrino oscillations? http://www-numi.fnal.gov/public/oscillations.html

LindsayJ
Do things look bigger under an electron microscope?

Chris White
All microscopes "enlarge" objects. Electron microscopes use electron waves to look at very tiny things, things that are smaller than the wavelength of visible light.

joe
what is particle physics?

Chris White
Particle physicists are people that study fundemental particles, like quarkes and leptons (electrons being an example of a lepton).

Guest
On the Fermilab website it says that the masses in the range of the MiniBooNE will expand our knowledge of the evolution of the universe. I was wondering what mysteries of our universe neutrino oscillations could help us solve.

Bruce Baller
Neutrino oscillations actually create more mysteries, since this effect doesn't fit into our standard picture of the standard model of particles. This is exciting!

Moderator
Luminosity in the Tevatron keeps going up, up, up! http://www.fnal.gov/pub/now/tevlum.html

Shabooty17
How do diverging and converging lenses work?

Chris White
Diverging lenses use refraction to bend light away from the lens axis, while converging lenses use refraction to bend light toward the lens' axis.

Rondo
Numi/Minos and Miniboone are both neutrino experiments, right? How are they different?

Bruce Baller
There are at least three types of neutrinos, muon neutrinos, electron neutrinos, and tau neutrinos. Maybe also sterile neutrinos? Numi/MINOS and MiniBooNE look for different oscillation mechanisms.

Moderator
The Story of the Neutrino: http://www.fnal.gov/pub/inquiring/physics/neutrino/discovery/neutrino_story.html

Cary
How much insight can you offer on the big bang

Chris White
This is a huge question.... can you be more specific?

Cary
Well I was wondering about the latest theories for the big bang, and how does your work relates to it or offer new information?

Chris White
This is a huge topic that would take many many hours to discuss. An excellent source for new info can be found by looking for recent results from the MAP satellite from the NASA web pages. These results have significant consequences for big bang theories.

Moderator
Fermilab Instructional Materials for Students and Teachers: http://www-ed.fnal.gov/trc/projects/index_all.html

Moderator
Physics is our mission, but buffalo may be Fermilab's main attraction for visitors. What are buffalo doing at a physics laboratory? Here is the answer: http://www.fnal.gov/pub/about/campus/ecology/wildlife/bison.html

Tiny
What are the properties of a neutrino? What are they exactly?

Bruce Baller
Well they are really really dinky. They apparently have some mass (since they are known to oscillate - SuperK experiment), but the mass must be far smaller than any other particle.

Ngraham
Could a change in the standard model give us insight into dark matter?

Chris White
Yes. We're not sure what dark matter even is, so anything new that we can discover may help in solving the dark matter problem. A change in the standard model means that we've learned something new.

Moderator
Just what do all of those scientists at Fermilab do? Learn more about Fermilab research: http://www.fnal.gov/pub/about/experiments/index.html

Moderator
Subscribe to Fermilabís free publication, FermiNews: http://www.fnal.gov/pub/ferminews/index.html

Shabooty17
What is the highest level of math does one have to take to be a physicist?

Bruce Baller
A good understanding of calculus is essential.

Moderator
Particle Physics for Regular People Ė Recommended Readings http://www.fnal.gov/pub/ferminews/reading.html

Chris White
In regards to the big bang, our work will help pin-down neutrino mass; however, neutrino mass only plays a minor role in cosmology.

Moderator
Current Status of Access to Fermilab: http://www.fnal.gov/pub/about/public_affairs/currentstatus.html

Moderator
These are programs at Fermilab that the Lederman Science Center offers for students: http://eddata.fnal.gov/lasso/program_search/search_programs.html

Rondo
So, what's it like being a neutrino scientist at Fermilab? Do you feel like "stepsisters" to the collider experiments?

Chris White
No way! The neutrino program is very exciting and complementary to the collider program.

Moderator
This is how seventh graders described scientists after they visited Fermilab: http://www-ed.fnal.gov/projects/scientists/

Moderator
Questions people ask about physics: http://www.fnal.gov/pub/inquiring/questions/index.html

Moderator
Learn more about Fermilabís Chain of Accelerators: http://www.fnal.gov/pub/inquiring/physics/accelerators/chainaccel.html

Moderator
Discoveries at Fermilab: http://www.fnal.gov/pub/inquiring/physics/discoveries/index.html

Ngraham
I noticed that among Fermilab's acheivements you discovered a quasar at a distance of 27 billion lights years from Earth. Have you found anything farther since and/or do you expect to?

Bruce Baller
I believe you are referring to the Sloan Digital Sky Survey. Sorry but we don't know much about what these folks are doing.

Seth
So what exactly is this neutrino that every one keeps talking about? Are people at Fermilab studying it?

Chris White
A neutrino is a very tiny particle that doesn't like to interact with "ordinary" matter like atoms. It is related to electrons.

Hakob
what kind of projects have been conducted so far?

Bruce Baller
Sorry Hakob. You need to ask a more specific question. There are LOTS of projects going on here.

Moderator
Fermilabís Founding Director, Robert R. Wilson, greatly influenced the design of the entire laboratory. Learn more about all of the interesting architecture at Fermilab: http://www.fnal.gov/pub/about/campus/architecture.html

Robert
I have heard that some black holes might be traversable (known as wormholes), and that the matter that keeps them open is called 'exotic matter.' How can this be true, if we have never found any exotic matter yet? If we do find a wormhole, will we be able to travel through it?

Chris White
Good questions. Theorists are people that imagine new things that may (or may not) exist in reality. Many of these theories are difficult to test, so it is hard to answer your questions directly. Sorry, I'm not a black hole expert.

Pammo
Is particle physics more closely related to chemistry or astronomy?

Bruce Baller
There is a much stronger connection with astronomy, because the energy scales are similar. Chemistry deals with low energy phenoma - electron transitions at the atomic scale. Particle physics deals with interactions at a much smaller distance.

Rondo
How did each of you get involved in neutrino physics?

Chris White
Neutrino physics is one of the "hot" areas in HEP today. Fermilab is developing a new neutrino program and I decided to participate.

Moderator
Many wonderful brochures and bookmarks about high-energy physics are available to order online: http://www.fnal.gov/pub/about/public_affairs/brochures.html

Seth
What types of experiments are you doing with neutrinos?

Chris White
Specifically, we're trying to study neutrino oscillations, where one type of neutrino morphs into other types of neutrinos.

Shabooty17
Does fermilab perform labs with splitting atoms?

Bruce Baller
We sometime split hairs... Never mind. Yes. We split atoms all the time. More accurately, we split atomic nuclei.

Shabooty17
What is HEP?

Moderator
HEP stands for high-energy physics.

Ngraham
Why does the MiniBooNE have one detector while the BooNE has two?

Chris White
Mini means smaller. MiniBooNE is a smaller version of a larger detector. BooNE will be built if exciting stuff is discovered with MiniBooNE.

Moderator
Acronyms of High-Energy Physics http://www.fnal.gov/pub/inquiring/more/acronyms.html

Sinh
I read about quantum fluctuation of vacuum and Zero Point Energy. Is there any experiment that confirms or disproves such hypotheses?

Bruce Baller
Yes. The Casimir effect demonstrates the existence of vacuum fluctuations. This is a force (tiny, tiny) between two parallel plate that are closely separated.

Moderator
Internships in Science Communication http://www.fnal.gov/pub/about/public_affairs/internship.html

Rondo
So what were you working on before, Chris?

Chris White
I've done a number of things: hadron physics at Brookhaven lab, tau physics at CLEO II, CVD diamond detector development, and Hyperon physics at Fermilab.

Moderator
Available materials from the Office of Public Affairs that you can order online: http://www.fnal.gov/pub/about/public_affairs/materials.html

Sinh
Have you ever observed neutron-neutron fusion?

Bruce Baller
This isn't something that we study at Fermilab. It would take very low energies to study this. We are the high energy folks.

Seth
So in your experimentations with neutrinos what are some new things you have discovered?

Chris White
Our experiments are either in the building phase or (in the case of MiniBooNE) only just beginning. In the world of neutrinos, the community has discovered neutrino oscillations.

Shabooty17
What does quantum physics deal with?

Chris White
Quantum physics deals with the way particles interact at the sub-atomic scale.

CCary
Ok, back to the big bang. Those WMAP pictures on Nasa's website say that the universe was once smoothed out, but somehow got pulled back in and created wrinkles that are now galaxies. What force did this?

Bruce Baller
Gravity did it.

CCary
Gravity from what?

Bruce Baller
If all of the mass in the universe is spread out smoothly, then every particle sees no net force since it is pulled from all sides. If there is some clumpiness, the nearby particles will be pulled closer together by gravity.

Moderator
What is particle physics all about? http://www.fnal.gov/pub/inquiring/matter/index.html

Sinh
Do you think that space is also quantized?

Chris White
I'm not sure. I know that it is expanding though.

Moderator
Learn about the MINOS Mural Project: http://members.macconnect.com/users/g/giannetti/pages/mural.html

Moderator
National Geographic: Scientists Try to Pin Down Elusive Neutrinos http://news.nationalgeographic.com/news/2002/05/0521_020521_TVneutrinos.html

Justin
How does a proton accelerator work?

Chris White
Protons are "accelerated" using electric fields. Magnetic fields are used to bend the protons and steer them to where we want them.

Moderator
The Minos Experiment: Mining the Imaginations (Streaming Video) http://vmsstreamer1.fnal.gov/VMS_Site_02/VMS/MINOS/MINOS.htm

Sinh
I have read on the internet the conversation between Professor Steven Weinberg and Dr. Harold Puthoff. One says that the Zero Point Energy in space is very small. The other thinks that the energy in one cupful may be enough to boil the oceans many times over. Who is right, do you think?

Chris White
Sorry, I'm not familar with this conversation.

Moderator
Learn more about research at Fermilab http://www.fnal.gov/pub/about/experiments/index.html

Ngraham
Has the MINOS detector been completed? If not, what added capabilities will you have once it is?

Bruce Baller
The detector will be completed in a few months. There are about 14 detector planes left to install (out of 454 total). The detector is made in 2 parts (supermodules), and each one has a magnet coil. This is the first underground detector that can detect the sign of the charge of muons. This should provide new information on neutrinos and anti-neutrinos.

Rondo
Chris, you mentioned that space is expanding... They've been having some big shake ups regarding the standard model of the universe, correct? Is that a parallel to the shift you're seeing? (I'm sorry if that doesn't make any sense...)

Chris White
The universe is expanding. This is a consequence of the big bang. All the recent evidence supports the big bang model. The "big shake-up" you're refering to is probably the idea of Dark Energy. No one has any idea what dark energy is or where it comes from... stay tuned...

Rondo
I think I'm referring to the discovery that the universe's expansion is actually *accelerating* rather than *decelerating*. Wasn't that a pretty big coup?

Chris White
Yes, and the accelerating universe is suppose to be due to "dark energy". Dark energy is something that we know nothing about...

Moderator
New neutrino lecture series at Fermilab! Nu Horizons: Neutrinos Off the Axis http://www.fnal.gov/pub/events/nuhorizons.html

OmicronDC
Are you interested in applying Fuzzy Logic to problems, or do you prefer probability?

Bruce Baller
I have heard the term fuzzy logic, which I probably don't understand enough about to answer. We deal with probabilities.

Moderator
How many different languages are spoken at Fermilab? http://www.fnal.gov/pub/about/faqs/languages.html

Seth
So what is a muon?

Bruce Baller
A muon is like a fat electron. By fat I mean it is heavier than an electron.

Moderator
HEPAP Publication: The Science Ahead, The Way to Discovery http://www.fnal.gov/pub/forphysicists/hepapbook/index.html

CCary
If particles in space are pulled together by each other, rather than the central force where the Big Bang originated, that would mean that it isn't spherical, correct?

Chris White
If we assume a symetric origin, then space is spherical; however, the observable universe if only a tiny fraction of the total universe, so we don't know for sure the exact topology.

Moderator
On this webpage you can see Live Events from the detectors of CDF and DZero http://www.fnal.gov/pub/now/live_events/index.html

Anthony
What evidence do we have that the universe is expanding?

Bruce Baller
The clearest evidence is the Doppler effect. The frequency of light from distance objects is shifted the further away they are.

Moderator
On the Fermilab website you can find a High Energy Physics timeline, explaining who discovered what and when. This is the url: http://www.fnal.gov/pub/inquiring/timeline/index.html

CCary
is there another way to detect the center of the universe other than the motion of galaxies, say, wave patterns or electromagnetic emissions... or maybe something else

Chris White
in fact, there is no center. All points look the same. This is a cool consequence of the big bang model.

Moderator
Here is an online photo collection that introduces Fermilab in all its facets. Here is the link: http://www.fnal.gov/pub/about/whatis/picturebook/index.html

Sinh
Is it possible that we can obtain fusion energy with cheaper cost as compared to fossil fuels?

Bruce Baller
This is a hard question to answer. The devil is in the technical details and the economics. A lot of research is required before these questions can be answered. I'm not sure that we have even reached the break-even point yet.

Moderator
Curious about Fusion Energy? Learn more about the ITER project: http://www.iter.org/

Seth
We have talked about the doppler effect in regards to sound, so how does light go with the doppler effect? And how does it prove that the universe is expanding?

Chris White
Distant galaxies are all red-shifted with respect to us. This means that they are ALL moving away from us. This is only possible if the universe is expanding.

Moderator
What is the Tevatron doing right now? Check the Tevatron status: http://www-bd.fnal.gov/servlets/d11?project=outside

Anthony
Could there be one central point where gravity is pulling the universe to?

Chris White
I suppose that this is possible.

OmicronDC
I have read claims that scientists have slowed light. Is Einstein's theory of relativity still valid?

Bruce Baller
I have read about this, but don't know the details. Was this observed in a Bose-Einstein condensate?

Moderator
Virtual Tour: The next best thing to visiting Fermilab in person. http://www.fnal.gov/pub/about/tour/index.html

Moderator
Here's another great High Energy Physics site: http://particleadventure.org/particleadventure/

Moderator
And a list of other institutions: http://www.hep.net/sites/directories.html

Rondo
Can you explain what "red-shifted" means?

Chris White
Red-shift is when a wave is doppler shifted to a longer wavelength. This occurs when objects are moving away from each other. blue-shift is when wavelengths are shortened due to motion toward each other. Note that red is a longer wavelength than blue.

Shabooty17
Where is Femilab located?

Moderator
Fermilab is located in Batavia, IL about 45 miles to the west of downtown Chicago.

Sinh
Does Fermi lab accept students from overseas to study there?

Bruce Baller
Yes, we do all the time. I assume that the student is associated with a university, college or institute. A senior member of this institution usually mentors the student and provides funds.

Moderator
Here's a page of Frequently Asked Questions about Fermilab: http://www.fnal.gov/pub/about/faqs/index.html

Moderator
Director Michael Witherell's vision for the lab: http://www.fnal.gov/pub/about/directorsoffice/index.html

weetodid09
Is it possible to increase the velocity of light?

Chris White
Einstein said that the speed of light in a vacuum is a fundemental constant equal to 3.0 times 10**8 m/s. The speed of light in materials is reduced by the index of refraction, meaning that light moves slower in matter than in a vacuum.

Moderator
Who was Enrico Fermi? http://www.fnal.gov/pub/about/whatis/enricofermi.html

OmicronDC
I have read articles detailing anti-proton propulsion systems. Do you believe such systems will prove efficient?

Bruce Baller
That's a hard question to answer. You need a rocket scientist to answer it.

Moderator
Fermilab produced its first high-energy particle beam on March 1, 1972. Since then hundreds of experiments have used Fermilab's accelerators to study matter at ever smaller scales. Here an overview of the top ten achievements so far. http://www.fnal.gov/pub/inquiring/physics/discoveries/index.html

Moderator
Sign up for the Interactions.org high-energy physics news wire: http://www.interactions.org/

Cary
What do you measure when you collide to nuclei?

Chris White
When we "collide" two particles (like two protons) we are studing the way in which the particles interact. We study what they are made from and we even produce new particles as a result of the collisions.

Moderator
We have VideoNews and streaming video of lectures and colloquia. Here is the url: http://www-visualmedia.fnal.gov/VMS_Site/s_videostreaming.html

Sinh
I read about a fellowship program from Vietnam Education Fund, funded by the US goverment. May I apply to get support to study at Fermilab?

Bruce Baller
I don't know enough about this to answer. Perhaps if you sent mail to the Fermilab User's Office they could help. I believe that you need to be enrolled as a student at a university or college for this to be possible.

Moderator
QuarkNet is a research collaboration between high school students, teachers and particle physicists. This is the QuarkNet website: http://quarknet.fnal.gov/

Hakob
Has fermilab done any experiments in search of 5 quark exotic baryon state?

Chris White
I've done a quick search of the Fermilab web site and didn't come-up with anything. Someone may have, but I'm not sure. I haven't done any research in this area and there are lots of things that get researched here at Fermilab!

Cary
Do protons conserve momentum when they collide?

Bruce Baller
They certainly conserve energy. Momentum is conserved only if the collision is elastic - think billiard balls.

weetodid09
Is there really another solar system that seems to be similar to ours, which might indicate aliens?

Chris White
No direct evidence, but strong circumstantial evidence.

Moderator
Safety and the environment at Fermilab: http://www.fnal.gov/pub/about/safety/index.html

Anthony
What are the good and bad consequences of colliding protons?

Bruce Baller
That depends on what you want to see...

Moderator
Mark your calendars! The next Virtual Ask-a-Scientist will be Thursday, June 5 from 7-9 Central Time. The featured scientists will be physicist, Mike Clements, of Fermilabís DZero experiment, and tunnel engineer, Chris Laughton, of Fermilabís NuMI-MINOS experiment.

Sinh
Until now, can Physicists obtain more produced energy than the quantity spent to make fusion? That means a gain ratio more than one?

Bruce Baller
I don't think that fusion experiments have reached the break-even point. Maybe they have but the gain isn't significant.

Shabooty17
Has Fermilab developed technology to discover extraterresterials?

Bruce Baller
No, dang it. I wish we could work on cool stuff like that.

Anthony
How would man be able to see the furthest planets, if ever?

Chris White
We look at the wobble of distant stars, or the luminosity variation as the planets pass in front of the stars. We can onlt search for planets that are very close to Earth (in our galatic neighborhood).

weetodid09
How far away is that solar system?

Chris White
No solar system similar to our's has been directly observed.

Moderator
Streaming Video: Is Anybody Out There? http://vmsstreamer1.fnal.gov/VMS_Site_02/Lectures/Colloquium/Werthimer/index.htm

hakob
Have there been any top quark cooler transparency and cp violation experiments?

Chris White
No top quark color transparency - lots of CP violation experiments. Many of the current HEP experiments study CP violation in one form or another.

JASMINE
What can you tell me about light refraction?

Chris White
n1sin(theta1) = n2sin(theta2). This is the law of refraction. Light refracts when it moves from one index of refraction to another.

Seth
In class we have talked about the doppler effect with concern to sound, but how does it concern light, and how does it help us understand that the universe is expanding?

Bruce Baller
The doppler effect works on light the same way that it works with sound. Stars that move away from us are "red shifted" that is the frequency of light is shifted lower. Trains that move away from us make sounds that are lower in pitch. The same deal!

Cary
Theoretically, if I were to accelerate to the speed of light, or even approach it, what would I see?

Chris White
A lot of really cool stuff... Hollywood 3-d effects stuff.

Moderator
Learn more about the Soudan Underground Laboratory: http://131.212.67.203/index.htm

weetodid09
Last year I heard something about absolute zero, something about making a proton stop moving all together, has there been any advancment in this?

Bruce Baller
Even if you reach absolute zero and stop the proton, it will still wiggle around due to quantum fluctuations. You can't stop the wiggles. This is really low energy stuff that we don't work on at Fermilab.

hakob
How is the progress so far on CP violation experiments?

Chris White
CP violation has been observed in meson decays, but not in baryon decays. It is also being considered in the neutrino sector.

Anthony
If a man were to speed up to the speed of light, wouldn't that affect the body in some way, either beneficially or adversely?

Chris White
I wouldn't try this at home...however, if you accelerated slowly, there's no reason why you can't travel near the speed of light (with respect to the Earth). It would take LOTS and LOTS of energy, but is theoretically possible.

Seth
Does the doppler effect explain spectra?

Bruce Baller
Yes. All stars contain a certain amount of hydrogen, which emits light at various wavelengths as it is heated in the star's "atmosphere". When this light is detected on the Earth, astronomers can match the expected wavelengths which have been shifted lower in frequency. The amount of shift measures the speed and therefore the distance.

Moderator
What is the difference between NuMI and MINOS? http://www-numi.fnal.gov/public/numiproject.html

Mr. Aladdin
Volume expansion was a question in my physical science class. Can you explain it to me?

Chris White
As objects heat-up (become hotter) they expand. This is because the molecules are moving faster and push harder against their neighbors.

weetodid09 If I wanted to calculate how a golf balls spin affected the lift, how would I do it ?

Bruce Baller
This is a turbulent flow problem. The dimples on the ball are there to induce turbulent flow quicker. I doubt that there are analytical solutions to this problem. I believe that these effects are simulated on computers nowadays.

Sinh
I read on the newspapers that within 40-50 years, the world will run out of oil. Do you think that in such short time, the Physicists may find ways out to replace fossil fuels?

Chris White
As the oil runs out, there will be economic incentives to find replacements. Only then will the governments of the world take this problem seriously. Yes, alternatives exist.

JASMINE
Right now our class is learning how to draw light diagrams, any tips to help make it easier?

Chris White
Use a good ruler and draw straight lines! More seriously, draw lines through the focal points and through the center of the lens.

Seth
Is there any way that you use waves in your experiments that you are conducting or have conducted?

Bruce Baller
Unfortunately not. We don't usually bother detecting the light frequency, but the intensity.

Sinh
What is the minimum energy to make two colliding protons be fused?

Chris White
Fission of 2 protons can occur at about 1-10 million degrees Kelvin.

Shabooty17
Does light intensity affect distance?

Chris White
Short answer, no.

Cary
Could your study of neutrinos some day benefit the design of future weaponry?

Bruce Baller
I suppose it is possible. Basically anything can be used as a weapon. I am considering using the computer mouse on my associate here...

Mr. Aladdin
When you put water in the freezer it expands as well, Mr. White. This means they do expand as they become colder - so does bismuth.

Chris White
There are very few exeptions to the rule. Water is one such exception.

Moderator
Did you know that there is an exceptional variety of birds living, breeding on Fermilab grounds? Here is a link to our "bird pages": http://www.fnal.gov/pub/about/campus/ecology/wildlife/birds.html

JASMINE
Can someone explain exactly what the difference is between light reflected through a concave and convex lens?

Bruce Baller
There isn't any difference in the light, except in the direction it goes after it leaves the lens. I'm not sure I understand your question. Please try again.

Mr. Aladdin
Why do water and 3 compounds expand as they get warmer and colder?

Chris White
It is due to their unique electronic structure.

Moderator
Fermilab has a big audience that visits the lab for cultural events. On this page you can see what we offer: http://www.fnal.gov/pub/events/culture.html

Cary
What do you see as the next frontier in outer-space propulsion - even liftoff propulsion of rockets, etc.?

Chris White It is probably best to ask NASA. How about anti-matter propulsion?

Moderator
Fermilab's art gallery has regular shows: http://www.fnal.gov/pub/Art_Gallery/

Sinh
But alternatives now cannot fully replace fossil fuels, can they?

Bruce Baller
There are other alternatives to fusion, i.e. fission, solar. Can they "fully replace" fossil fuels? Change will be required when the Mother Earth's tanks run dry.

Seth
What are some interesting studies that have to do with waves that a physicist could conduct?

Chris White
Current or classical? There have been many interesting experiments in the past. Also, sub-atomic particles have wave properties, so I suppose all HEP experiments are also wave experiments.

Sinh
So what is the minimum distance between two protons where they start to attract themselves at 1-10 million Kelvin?

Bruce Baller
I believe it is about 1 to 2 fermi.

Mr. Aladdin
What is electronic structure? Is it a kind of molecular structure?

Chris White
Electronic structure refers to the shape of the electon orbitals (the probability ditributions for the electrons near the nucleus).

Shabooty17
Does color light have any affect on it refraction through concave and vex lens'?

Bruce Baller
Yes. Each section of the lens is like a prism, which diffracts red light more than blue light.

anthony
The sun is a light source and rays of the sun are harnassed for many purposes; is there any way to amplify the sun's rays for the purposes of a better power source?

Chris White
You can't amplify the sun's rays. You can concentrate them, but not amplify them (there is a difference). Concentrated rays can be used to produce electricity or heat water for heating homes.

Sinh
Sorry, I am not familliar with fermi. Please change one fermi to meters or inches scale.

Chris White
1 fermi is 10**-15 meters

weetodid09
If black holes aren't really visible, where you can only see the matter around them, then how did the theory come about?

Bruce Baller
After you understand that gravity bends light, it is a small step to imagining a sufficiently strong gravitational field to trap the light in an "orbit".

Cary
What exactly is the problem with cold fusion and is there a similar or different approach to its theory?

Chris White
Cold fusion gets something for nothing. There's no such thing as a free lunch in physics.

weetodid09
When colliding two atoms, is there a safety hazard?

Chris White
It depends on the energy. At low energy they just bounce off each other. At high energy, the collision can create additional charged partciles. Note that these collisions happen naturally all day and night due to cosmic rays (protons from outer space hitting the atmosphere).

JASMINE
We are learning how to graph ray diagrams and I'm just looking for a way to understand it better. I guess what I'm trying to ask is why, when using a concave lens, the light reflects through the lens in two different directions, one ray above and one below the normal (correct)? And whay, when using a convex lens the light ray ends up below the normal?

Bruce Baller
This is really hard to answer in words. I recommend that you draw some pictures of light entering and leaving a glass surface. The angle of entry and exit depends on the index of refraction. Sorry I can't help you more...

Seth
Aside from my question about HEP experiments, how will neutrino oscillation experiments contribute to the scientific world?

Bruce Baller
The short answer is that neutrino oscillations demonstrate the first physics that is outside the standard model.

hakob
How possible is it to creat a runway for aircrafts in outerspace with magnetic fields to propel the aircraft?

Chris White
The required energy would make such an endeavor impractical, but it is theoretically possible to use induction as a means of propulsion.

Sinh
We have a saying " Late jump when the water rises so high". If the governments act only until Mother Earth's tank runs low, is it to late? For we know that any change needs a transitional period even if we may find out practical alternatives to fossil fuels?

Chris White
There are alternatives available. We will need to change the way in which we use energy, but I believe that man-kind will adapt to reduced availability of fossil fuels.

Moderator
How do scientists find those small particles? http://www.fnal.gov/pub/inquiring/matter/smallest/index.html

OmicronDC
Which classical Scientist do you believe has influenced you and your work the most?

Bruce Baller
I particularly admire Lucretius (3 AD?) who was an Atomist. I admire his thought experiments to explain why the universe is composed of atoms. Also, the language is lovely. The treatise begins with an ode to Venus.

Moderator
Reasons to support high-energy physics: http://www.fnal.gov/pub/inquiring/matter/whysupport/index.html

Moderator
Standard model discoveries: http://www.fnal.gov/pub/inquiring/matter/ww_discoveries/index.html

weetodid09
Are there any nebulaes in our galaxy?

Bruce Baller
I am not an astronomer but I think the answer is yes. A nebula is just a big clump of gas with a few stars thrown in for special effects. Yes?

Moderator
A total of 53 species of butterflies have been identified at Fermilab. Here is the complete list: http://tdpc02.fnal.gov/peterson/tom/Butterflies/FermilabButterflyTable.html

JASMINE
Are there any new exciting projects coming up at Fermilab soon?

Chris White
The NuMI beamline is being constructed. The MIPP experiment is being built. The collider is running (providing proton-antiproton collisions for the D0 and CDF experiments) the MiniBooNE experiment is taking data, and the theory groups are cranking out lots of exiting new theories. The Fermilab softball season starts tomorrow as well.

Moderator
What is Fermilab all about? http://www.fnal.gov/pub/about/whatis/index.html

Mr. Aladdin
Thank you for helping with our questions. Some of them were my students' questions. I wish I knew about this session ahead of time so that I could tell them to be here. I am a Science teacher at Fulton Science Academy where future Scientists have many questions for you.

Chris White
Send them to IIT where I'm a physics professor!

Moderator
The Lederman Science Center has excellent resources for teachers. http://www-ed.fnal.gov/trc/trc_puzzle.html

Mr. Aladdin
The probability of electrons are so hard to understand. I took two courses on them, and I still don't understand. Why does water obey many rules as other compounds do like it is different than reactants those make water. Current science and technology still is not sure about movements of electrons ( except their possible places) right? They are also tiny particles. We are made of atoms where electrons spin around the nucleus. How come we can touch objects? Do we have electrons with extremely high frequency?

Bruce Baller
We are more sure about the movement of electrons than we are about the stock market. Electron motion at the microscopic scale is probabilistic, but one can calculate these probabilities exceedingly well. When we touch objects, our electrons are repelling each other. Electrons don't have a high frequency. Electrons may emit light at a high frequency if they are severely accelerated.

Moderator
Online instructional material for teachers courtesy of the Lederman Science Center: http://www-ed.fnal.gov/trc/projects/index_all.html

Moderator
Particle Physics for Regular People Ė Recommended Readings http://www.fnal.gov/pub/ferminews/reading.html

Seth
What is Fermilab? So far I have seen that you study butterflies, neutrinos, and other things. What is your main focus?

Bruce Baller
Butterflies? We also have buffalo and native prairie grasses. These are a side light to the main theme of the lab, however, which is high energy physics research - trying to figure out what makes the universe tick (and what makes it tick).

weetodid09
If there were no stars around the nebula, could it be confused with a blackhole?

Chris White
Nebulas are regions of gas and dust. Black holes are ultra dense objects. Nebulas come in many varieties and are not typically mistaken for black holes.

Moderator
Questions about black holes: http://www.fnal.gov/pub/inquiring/questions/blackholes_info.html

Dblduceaction
In what environments does light act as a particle, and in what others does it act like a wave?

Chris White
Photons are both particles and waves simultaneously. They have properties of both at all times. I can't give you hard and fast rules about when they act like waves and when they act like particles because there are too many exceptions (they are simply both).

Sinh
What happens if fusion happens in a closef chamber? Is there any effect that is similar to LAZER effect where the travelling electromagnetic waves produce LAZER?

Bruce Baller
The products of fusion are photons and lots of moderate energy neutrons. If you don't have a thick walled chamber, all your fusion products leak out. In order to create a laser, you need to bounce the particles back and forth so that they interfere. Fusion products are to high energy to make them bounce back.

Moderator
FermiNews: Fundamental Research with Particle Accelerators http://www.fnal.gov/pub/ferminews/ferminews03-04-25/p4.html

Cyndi
Could one create a black hole with a large enough particle accelerator? And if so, how exactly does this work? How large or strong would the black hole be?

Chris White
I don't think so. To make a black hole you have to have negative total energy (or else the mass won't be bound to itself). I'd have to ask a theorist to get a more detailed answer.

Sinh
Can they use quantum mechanics to calculate exactly the emission spectrums of other elements other than Hydrogen?

Bruce Baller
I am not sure. The calculation is hard enough to do for hydrogen. When you get into few-body problems (like solar systems with heavy planets and light atoms) there aren't any simple approximations.

Moderator
FermiNews: New Species Introduced to Fermilab: http://www.fnal.gov/pub/ferminews/ferminews02-11-01/p3.html

Moderator
Questions and Answers about black holes: http://www.fnal.gov/pub/inquiring/questions/quesuniverse.html

JacSlac
OK, I know there are four basic forces but I can't remember what they all are and what they do?

Chris White
Gravity, electro-magnetism, magnets and electricity. The weak force mediates radio-active decays. The strong force holds the nucleus of atoms together.

weetodid09
Do black holes have a temperature?

Bruce Baller
You bet. Everything has a temperature. It is a measure of entropy .

Moderator
Questions and Answers about special and general relativity: http://www.fnal.gov/pub/inquiring/questions/quesrelativity.html

Moderator
A total of 273 species of birds have been recorded at Fermilab. Here is a diary of recent bird sitings at Fermilab: http://www.fnal.gov/ecology/wildlife/diary.html

Cyndi
How does a particle accelerator create a new element? Are there restrictions, or can just any element be made?

Chris White
You're mixing two different ideas...to make new elements, you need to start with a heavy element and add more protons and neutrons until you make something new. This is usually done by attempting to merge two atoms (like gold) into something new. At particle accelerators, we collide particle to create new particles. This is possible because Einstein told us that mass is energy. We simply use collisions to convert energy into mass (new stuff).

Mr. Aladdin
If electrons repel each other, the probability to reach the nucleus would be so hard. This means we hardly have a nuclear reaction just by touching right? By the way thank you for inviting us. I will tell my students about your invitation

Bruce Baller
I am not sure I understand your question. Electrons surrounding the nucleus are repelling each other, but are attracted to the protons in the nucleus. The only thing that keeps them from "getting sucked into" the nucleus are quantum effects.

Moderator
Theory at Fermilab: http://www.fnal.gov/pub/inquiring/physics/theory/index.html

weetodid09
Is time travel considerable, or is it just a sci fi thing?

Chris White
You can travel to the future (I can tell you how) but you can't go back again...

Cyndi
I heard that if something the size of 10,000 Jupitors was pulled into the center of a black hole, it would be crushed to the size of the head of a needle. Is this true?

Chris White
Yes, maybe smaller....

Moderator
To get our protons on the way we use a "chain of accelerators". Here is more information: http://www.fnal.gov/pub/inquiring/physics/accelerators/chainaccel.html

Guest
Does the standard model have particles for all the forces in the force carriers section?

Chris White
Yes. Seth
Which of the four basic force are you most concerned with in your experiments with neutrinos?

Chris White
The weak force. Other than gravity, this is the ONLY force that neutrinos feel.

Moderator
How does an accelerator work? http://www.fnal.gov/pub/inquiring/physics/accelerators/index.html

OmicronDC
Do you believe a "Theory of Everything" will be discovered, or is everything simply too complex?

Chris White
Yes, someday. I believe in science.

Moderator
Learn about astrophysics at Fermilab: http://www.fnal.gov/pub/inquiring/physics/astrophysics/index.html

Seth
What type of methods do you use in your experiments with neutrinos? Is it like Jefferson Lab, where you speed up electrons and collide them with each other? I think that is what they do.

Bruce Baller
Sorry, I don't understand this question. We create neutrinos to study their properties. They are such wimpy things that it takes a lot of them to make any measurements. You can't convince them to stay in a beamline like protons or electrons.

pat_supa
How fast can you accelerate a particle?

Chris White
If the particle has mass, then it can be accelerated to 0.9999999999999999999999999999999999999999999999999999999999999
9999999999999999999999999999999999999999999999999999999999999999
9999999.....times the speed of light in a vacuum.

Moderator
HEPAP Publication: The Science Ahead, The Way to Discovery http://www.fnal.gov/pub/forphysicists/hepapbook/index.html

Guest
Is the intensity of light in a laser caused by interference when the light is reflected in the chamber, or does something else allow it to maintain a high intensity over long distances?

Chris White
In a laser, atoms are "pumped" into an excited state and then enticed to de-excite in a coherent fashion creating an intense, coherent pulse of light.

Sinh
How can you produce the protons in vacuum chambers to make them collide?

Chris White
The protons are taken from a bottle of hydrogen gas.

henry
Could the refractive index of a material Ė a pure glass? Ė be used to determine if that materialís density changes as gravity changes? That is, would there be a measureable change in the refractive index between measurements take at sea level and measurements taken in orbit? If so, what might the results indicate?

Bruce Baller
There is a difference in the refractive index of air at sea level and the vacuum of space. What do you mean by what the results might indicate. Sounds like a question from a final orals exam.

Cyndi
What exactly is the holding back the development of cold fusion? Is it theoretically possible to obtain in the next 50 years?

Chris White
Don't hold your breath.

Moderator
We have about fifteen minutes left to the chat session. Please submit your final questions now. Don't forget to check back for tonight's transcript in about a week or two.

Sinh
If the energy is too high for the particles to bounce back in fusion , can we use a "thick enough wall of high electric field" to bounce the particles back? That means we make may different layers of high electric field wall to bounce back the particles?

Bruce Baller
Nope. In a laser, the light is reflected back without any energy loss. The energy of the fusion products are high enough that the interactions with the wall are inelastic. Good idea, but it won't work.

kaleb
What is the energy range when the particles collide?

Chris White
When the protons collide with anti-protons, the collision has approximately 2 TeV of energy. That's equivalent approximately to the mass of 2000 protons.

Moderator
Here are some outreach materials about MINOS: http://www-numi.fnal.gov/public/outreach.html

Cyndi
What exactly is the hold up on cold fusion, lack of funding or is it just too advanced?

Chris White
Cold fusion is held back by bad science. There is no scientific reason to believe that it will ever work. It's pie-in-the-sky science.

Moderator
Fermilab Lecture Series Ė Streaming Video: Fermilab's Particle Accelerators: Past, Present and Future http://vmsstreamer1.fnal.gov/VMS_Site_02/Lectures/LectureSeries/Foster/index.htm

OmicronDC
Can Fermilab store anti-protons, or must they be created and immediately used?

Chris White
They can be stored for short periods of time (measured in hours, not weeks).

Mr. Aladdin
My question was about the possibility to reach nucleus which might make changes in the nucleus. Lets say we hit a bullet to a steel wall so fast.Electrons in the bullet repel electrons in the steel. Right? Isnt there a possbility for a nuclear reaction where electrons werent able to repel each other enough?

Bruce Baller
Yes, I understand. Electron-electron scattering experiments have been done for many years, because electrons are point-like. When they collide with each other, the repulsive force between them gets high enough that new particles and anti-particles are created. This isn't strictly called a nuclear reaction since there is no nucleus involved. Does that answer your question?

Moderator
Order tickets now for the Fermilab Summer Arts Series: http://www.fnal.gov/culture/arts_series.shtml

weetodid09
What is the major missing element in the research of physics today? What one important thing do we not know that could help solve other things?

Chris White
Ah, this depends on who you ask! Every physicist has their personal opinion (usually about their own research). I think dark-matter and dark energy are exciting, as is the entire neutrino sector in particle physics. Superconductivity is another interesting area of research.

weetodid09
Dark matter? In relation to space ?

Chris White
Dark matter is stuff than responds to and produces gravity (like ordinary matter) but is not visible (for whatever reason). The best idea today is that dark matter is due to WIMPs (weakly interacting massive particles).

Guest
In combustion engines we need a close chamber to have a quick combustion (chain reaction) of hydrocarbons? Do you think we also need some kind of "close chamber" to contain the particles and make a "chain reaction" of fusions?

Bruce Baller
The energy density required for fusion is so high that a physical chamber as you imagine it would not survive. The confinement mechanism is usually a magnetic field.

henry
The refractive index of a given piece of glass should be constant - yes? Well, if it, the index, changed with the a difference in gravity that would be meaningful, or so it seems.

Bruce Baller
Sorry I was reading too much into your question. OK, imagine that the index of refraction changes, due to density changes. Why would this be meaningfull?

Guest
Here I am saying that the "wall" is a high electric potential field. In this way the particles may be reflected without "energy loss"?

Bruce Baller
I am missing the point of your question. Please re-phrase it.

Guest
Yes, thanks. I just called new form of particles and anti particles as a nuclear reaction.

Bruce Baller
OK. Are you happy with my response? I'm not sure I answered your question adequately.

weetodid09
Dark matter isnt visible by eye or at all?

Chris White
The effects due to gravity are observable, but not by "eye" because the dark matter doesn't appear to interact via electro-magnetism (it doesn't absorb or emit photons).

bird
If two neutrinos collided would they break apart or bond?

Chris White
Neither, they would likely bounce-off each other or create new particles, but they wouldn't bond. Also, we believe that neutrinos are fundamental, so there's no internal structure, so they can't break apart.

Moderator
Don't forget! The next Virtual Ask-a-Scientist will be Thursday, June 5 from 7-9 Central Time. The featured scientists will be physicist, Mike Clements, of Fermilabís DZero experiment, and tunnel engineer, Chris Laughton, of Fermilabís NuMI-MINOS experiment.

weetodid09
So where would you find dark matter?

Bruce Baller
Apparently dark matter surrounds us. Astronomers can detect the apparent existence of dark matter by measuring the rotation speed of galaxies and the distribution of matter (stars) within the galaxy.

Moderator
We are wrapping things up now for this chat session. Thank you everybody for participating tonight! You all asked terrific questions!

Chris White
Thanks for the questions.... see ya next time...

Bruce Baller
Goodnight!

Moderator
Goodnight Everybody!



last modified 5/22/2003   email Fermilab