Science Behind Interstellar Explained

If you’ve recently been to the movie theaters to see Christopher Nolan’s latest film Interstellar, you may have left the movie like “OMG,” but possibly also like “WTF?” Through the film’s storyline, the audience is introduced to a number of captivating yet complicated topics that former NASA pilot Cooper (Matthew McConaughey) and his team must tackle on their quest into unknown regions of space in order to save mankind.

To help demystify a few astrophysics-specific topics discussed in the movie such as using wormholes to travel to distant parts of the galaxy, the physics behind alternate dimensions, tidal forces caused by the gravitational pull of black holes, Einstein’s Theory of Relativity, and the physics behind aging at different rates explained by the famous Twin Paradox just to name a few, InstaEDU has teamed up with its own physics, astrophysics, and cosmology tutors to not only help shed light on these topics but to open a dialogue between you, the reader, and our experts who can help explain the answers that you’re looking for.



Here to answer questions about the physics of Interstellar is one of InstaEDU’s “Interstellar” tutors, Jessica K, PhD from University of California, Berkeley and astrophysics tutor on InstaEDU.


InstaEDU: In the movie, Cooper and his team travel through a wormhole to shortcut their travel through space to a far-off galaxy. Can wormholes really exist?

Jessica: Wormholes have never been observed in nature, and in fact most theoretical physicists believe they cannot occur naturally.  Wormholes do not violate any laws of physics, and in theory could be created by an advanced civilization.  But currently (as far as we know) they only exist on paper, not in reality.

InstaEDU: So what is a super massive black hole, like the black hole in the movie nicknamed Gargantua?

Jessica: Black holes are known to exist and there is even a black hole at the center of our Milky Way galaxy.  Black holes are simply a huge concentration of mass in a very small volume.  A super massive black hole is a black hole with a lot of mass in it (i.e. a million times the mass of our sun).

InstaEDU: In the movie, the space-faring team visits Miller’s planet, which orbits close to the black hole Gargantua, and finds that there is an actual difference of elapsed time between the time on that planet and on Earth (about 7 years on Earth to 1 hour on the foreign planet). How is this possible?

Jessica: Time is relative and our experience of time is not absolute but a function of how fast we are moving and the gravitational field we are in.  This has been verified experimentally by taking identical clocks and flying one in a jet plane (or putting one at a different elevation) and seeing how time passes differently for the two clocks.  Because the gravitational field near Miller’s planet was so huge (due to the supermassive black hole) they experienced time slower than people on earth who were in a smaller gravitational field.

InstaEDU: Is it really possible that Cooper, the main character in the story, could age slower than his daughter, Murph, who lives on Earth?

Jessica: Yes, this is possible and is commonly described in physics by the “Twin Paradox.”  The “Twin Paradox” could occur if one person (say, one of two twins) was in a dramatically different gravitational field than another person (the other of the two twins), or if one person moved much faster than another person. This would cause them to experience the passage of time differently and thus age at different rates relative to each other. So theoretically, two twins born on the same date could have different ages if one were to travel near the speed of light while the other stayed on earth.


InstaEDU: On Miller’s planet, the team experiences some monstrous tidal waves due to the tidal forces of the nearby black hole. Can tidal forces really be that strong?

Jessica: Tides are caused by the gravitational field at one side of a planet being different than another side of the planet.  On earth this is caused by the moon exerting a gravitational pull on the ocean water.  You could imagine that if the moon were a lot bigger this could cause bigger tidal forces and more dramatic waves.  However, the way the waves were visualized in the movie I don’t think is accurate.  It would be less of a “wall of water” and more dramatic changes in the depth of the ocean.  However it looks cooler the way they did it.

InstaEDU: Now on to the really good stuff. In the movie, Cooper ejects from his ship in the blackhole and lands in the event horizon where he encounters “The Tesseract” — aka the wormhole’s gravitational singularity. This place is represented as a place where the laws of space and time become infinite. First off, what are singularity and the event horizon? In theory, can a place like this exist where the fifth dimension is represented three-dimensionally?

Jessica: A singularity is the place inside the black hole where the gravitational field is so strong (due to an almost infinite density of mass) that the curvature of space and time become infinite.  An event horizon is the edge of a black hole.  Once you cross the event horizon you can not escape the black hole’s gravitational pull and are stuck inside forever.

In Interstellar the manifestation of the singularity is a place where one can navigate both time and space dimensions.  This is allowed by the strong gravitational field warping space-time onto itself.  In reality if such a place existed inside a black hole, any living thing would be ripped upon entering the black hole before getting to the singularity… or if they somehow got there, wouldn’t be able to escape to report on what they saw.  It’s hard to imagine with our current knowledge of the laws of physics how someone could take advantage of a tesseract-like place, even if it were to exist.

InstaEDU: Lastly, if someone wanted to learn more about topics like the ones presented in the movie Interstellar, where would you recommend that they start?

Jessica: Most of the topics from the movie can be understood by learning about Einstein’s theories of Special and General Relativity, which can be done using Youtube videos or renting some good books. Kip Thorne, who is a theoretical physicists from Caltech and an executive producer for Interstellar, also wrote a book explaining the science behind the movie adequately named “The Science Behind Interstellar.” You should also chat with tutors, like me, on InstaEDU that can tutor in topics related to the movie Interstellar!


Want to message with experts in the fields of astrophysics, physics, and cosmology? Connect with InstaEDU’s online Interstellar tutors and set up one-on-one tutoring sessions with your favorite tutors to learn more about topics discussed in the movie and in the astrophysics community overall.

What college admissions officers look for in your essay

Today’s post is by Bob Patterson, former Director of Admission at Stanford University, he has worked with thousands of students for the last 18 years of his career.

Your college application essay or personal statement is your one opportunity to introduce yourself to the admission board, and put a voice to your test scores and GPA. Writing a self-reflective deeply personal essay can be trying. What do college admissions officers really look for?


Can you write?

Fundamentally the essay should serve to show your writing skills. Writing is an essential part of college courses, and the application essay allows admissions officers to see if you will be able to meet the demands of the writing curriculum at their school. Your essay should be well organized and properly formatted, and free of grammar and spelling mistakes. Thoroughly proofread – don’t just spellcheck.

What will you bring to the college community?

This essay serves as a means to show what you can contribute to the college. Admissions officers want to see you as an active contributing member of your community. This doesn’t mean you need to have 1000 community service hours. A unique genuine interest in the arts, a sport or activity all serve to highlight something you can contribute to the campus.

Personal Reflection

To allow us to get to know you, your essay should include personal reflection. While the other areas of your application will speak to the breadth of your extracurricular activities, the essay should focus on revealing depth in one area. Write a genuine thoughtful answer to the prompt showcasing what motivates you and why. Be compelling.

When writing your essay, start early, be yourself, be honest, take a risk and keep focused.

Believe me, I have read so many generic essays that were well written but didn’t tell me anything about a student. Admission officers want to know you and what makes you unique. It is not necessarily about the experience but what your take away was when you returned. How did the person, event, or experience change or reinforce who you are as a person and how will you contribute to the campus?  Test scores do matter but not as much as you think. Hey, it is only a 4 hour test on one Saturday afternoon, and what you did in high school is so much more important.


Want even more college admissions help? Connect with Bob and other Chegg college admissions counselors.

So you failed a midterm – now what?

The awful feeling when you get back you midterm grade, and it wasn’t what you hoped for— we’ve all been there. Don’t let your test scores get you down; you can still pass the class. With a little pro-active studying, you’ll be able to take back your grade.


Identify Your Weakness

Cry, freak out, eat an entire pint of Ben & Jerry’s (no judgement). It’s okay to be stressed out and disappointed in your grade. Once you’re calm and clear-headed, look over your exam. Did you bomb the whole exam or just do poorly in one section? Did you totally misunderstand the assignment or just one part of the material?

Once you’ve zeroed in on where things went awry, you can plan a study strategy to get a better grasp on concepts come finals.

Take Advantage of Office Hours & Talk to Your Professor

No matter where you went wrong, you should start by meeting with your professor or TA. Ask them to review your midterm with you and help identify how you can improve. Most professors will gladly offer suggestions on how to boost your grade in the future. Discuss your areas of strength and weakness. Was your midterm an essay? Review your professor’s notes and comments and ask for advice on how to improve your writing and argument on the next assignment.

You can also ask about opportunities for extra credit in the class. Meeting with your professor is the first step in proactively saving your grade.

Use All Your Resources

Let’s be honest— every student could use a little extra help. Now that you’ve identified what you need to work on, use all your available resources to ace your future exams and assignments. Go to class, take notes and actually participate.

After class, re-evaluate your study habits. When you know you’re stuck on a concept, connect with a tutor who can help walk through the subject and make it easier to understand. Tend to procrastinate? Commit to meeting classmates to study at a specific time. Boost your writing grade by having someone review your papers before you submit them.

5 Tips to Stop Sunday Procrastination

It’s Sunday morning. You’ve made it to the library, your schedule is totally clear for the day, and you’re planning to make a major dent in your work for the week. Before you start, you just want to quickly check Facebook in case anyone has posted photos from that party last night…

Next thing you know, it’s 4pm and all you’ve done is open your stats textbook to the correct page. Don’t worry; we’ve all been there. To help you avoid those all-nighters, here are 5 tips to stop your Sunday procrastination:

Screen Shot 2014-10-29 at 1.37.34 PM

Split up the Work

It can be overwhelming to see all the work you have in front of you. Where do you even start? Your assignments can feel a lot less daunting if you break them down into smaller subtasks. Rather than thinking about an entire essay you need to write, it’s way more manageable to first focus on creating an outline.

Give Yourself a Break

No one can focus for hours at a time – you end up not working effectively. Heading to the gym, or even a brisk 5 minute walk outside the library will keep you refreshed, alert, and ready to jump back into studying. Another good idea is meeting your friends for a meal at the cafeteria – it’s a great break from the library and a chance to grab something other than coffee, redbull, and vending machine snacks.

Prepare to Focus

Don’t tell yourself that you can be productive while doing homework in your bed. Next thing you know, you’ll be re-watching the entire first season of Breaking Bad under the covers. Head to the library, a quiet study area, or at the very least, sit at a desk. With fewer distractions around and a focused mindset, you’ll be less inclined to procrastinate.

Treat Yourself

You need some motivation to keep focused on a grueling day of homework. Try rewarding yourself every time you cross something off your to-do-list or finish a task in the hour of time you gave yourself. Good study rewards could be checking your Instagram and other social media accounts, taking a lap around the library to chat with friends, or even watching a quick episode of your most recent Netflix addiction.

Use Some Self Control

If you can, keep that laptop closed! You’re going to get a lot less done if you’re scanning Twitter, Facebook, and Reddit every five minutes. If you need to use more drastic measures, try out “Self Control App” on the iTunes store. You can block your favorite, time-wasting websites and set a timer for how long they’re off-limits. Not even deleting the app will get those sites unblocked for you.

5 Study Snacks to Bring to the Library

The first day of the semester is a distant memory, and the library now feels like home. Eating certain foods can help you improve your study focus, retain more information and stay mentally alert throughout your gruelling study sessions. These brain food snacks will satisfy your growling stomach and help you get better grades.

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Binge on Blueberries

Evidence from Tufts University suggests that eating blueberries may help to delay short term memory loss, so all those flash cards won’t be forgotten the moment you walk into your exam.

Crunch Some Broccoli

Broccoli is a known source of vitamin K, which enhances brainpower and cognitive function. Pair it with some hummus to help keep you full longer and prevent any embarrassingly noisy stomach grumbles.

Treat Yourself To Dark Chocolate

Resist that Snickers bar in the vending machine, and stick to dark chocolate. Dark chocolate is jam-packed with antioxidants and has enough caffeine to help you stay awake. Plus, as an added bonus, the smell of chocolate triggers relaxation in the brain.

Go Nuts

Many types of nuts contain essential fatty acids to help boost your brainpower. They’re also high in iron to help increase your mental alertness and ability to retain information. And they’re easily transported and full of protein to help keep you full and uninterrupted.

An Apple a Day

Eating an apple a day will keep the doctor away, and it is also a great power snack for studying. Apple peels contain powerful antioxidants called quercetin that help enhance memory function.

Let us know what your favorite study fuel is!

Midterms are coming…

Midterms, like Halloween, are just around the corner. As much as you may feeling like hiding under the covers, there’s no need to hide if you’re prepared.

Midterms are almost always stressful. You live in the library and run on little sleep…and a lot of caffeine. Relax, take a deep breath, and follow these four helpful tips to overcome midterm craziness and ace your exams.

1. Study a little bit each day

Start early instead of waiting to cram the night before the test. This will allow you to study in small, manageable amounts — which helps you retain more information and reduces stress.

Commit to a short time window when you’ll study each day; even 15 minutes is better than nothing. This can mean organizing your notes, creating study guides, or completing practice problems.


2. Review past notes, assignments and homework

Which questions or assignments were particularly tricky? Which problems did you get wrong on past quizzes or tests? Go through each one to make sure you understand it.

3. If you need help, ask

Still stuck on a few things? Whether it is a problem that you just can’t solve or an an essay that you just can’t start, talk it through with someone. Find a friend in your class, stop by office hours, or connect with a tutor on InstaEDU.

4. Sleep

Get some sleep. SERIOUSLY, GO TO BED. Don’t pull an all-nighter.

10 Common Writing Mistakes

It’s 2am and your paper is due at 9am. Your eyesight is blurry from looking at your computer screen. All you want to do is finish and go to sleep. So you turn your paper in without proofreading.

Then you get your paper back: C+. C+? You look through your professor’s edits and come across this:

“The principle point of this paper is to explore the affects of whether on gorilla warfare in Asian.”

Don’t let this happen to you. Use this checklist to help avoid 10 common student writing errors.

1. Missing a comma

Commas and periods are the two most used punctuation marks, but commas seem to cause the most confusion. Are you using commas correctly? Have you written any sentences containing items in a series? When three or more items appear in a series, they should be separated from one another using commas. (The last comma is optional, though.)

Example: We’re out of milk, eggs, and cheese.

Bonus tip: Always use commas to set off names or titles of a person when directly addressing someone.

Screen Shot 2014-09-26 at 10.02.47 AM2. No comma after an introductory phrase

An introductory phrase provides background information and is usually followed by a comma.

Incorrect – While I was studying my roommate watched TV.

Correct – While I was studying, my roommate watched TV.

3. Using the wrong word

Whether/weather. Affect/effect. To/too. While all are spelled correctly, they each mean different things. Watch your words and don’t rely on spell check alone. Spell check may not see words which are misused, but spelled correctly!


4. Run-on sentence

Run-on sentences occur when a sentence contains two complete thoughts without the necessary punctuation to link them. Run-on sentences should be divided into separate sentences or joined by adding words or punctuation.

Example: Mr. Smith sent all of his kids to college, however, he has sacrificed his health working to pay for it.

Where the first comma appears, we should have used a period and started a new sentence.

5. Watch your verb tenses

All the verb tenses should work together in harmony.

6. Pronoun shift

This occurs when an author switches pronouns for no apparent reason. I > you > one

Incorrect – If you eat sensibly and watch your calories, most people will be able to maintain their weight.

Correct – If you eat sensibly and watch your calories, you should be able to maintain your weight.

7. Spelling Mistakes

Mistakes happen, but make sure you stop and review your writing for errors. Having someone else review your writing will also help ensure that all mistakes get corrected.

stop error

8. Its vs It’s

For many people, this is one of the trickiest grammar rules. Use its to mean belonging to it; use it’s only when you mean it is or it has.

It’s is a contraction for it is or it has. “It’s almost the weekend.” Its indicates possessive. “Every dog has its day.”

Its’ is never correct. Ever.

9. Double Negatives

You know the old adage ‘two wrongs don’t make a right?’ Well two negatives do make a positive.

Incorrect: I cannot hardly wait for the semester to be over.

Correct: I can hardly wait for the semester to be over.

double negative

10. Mechanical error with a quotation

“I wish we were at the beach”, Elizabeth says.

The comma should be placed inside the quotation marks.

This list has some brief example and explanations for you to use as reminders while you edit papers. Have a paper you’re struggling to format? Or just want another set of eyes to help you proofread? Connect with a great writing tutor now.