Dear Dr B: What do physicists mean by �quantum gravity�?

[Image Source: giphy.com]

�please could you give me a simple definition of "quantum gravity"?

J.�

Dear J,
Physicists refer with �quantum gravity� not so much to a specific theory but to the sought-after solution to various problems in the established theories. The most pressing problem is that the standard model combined with general relativity is internally inconsistent. If we just use

We understand gravity just fine, thank you.

Yesterday I came across a Q&A on the website of Discover magazine, titled �The Root of Gravity - Does recent research bring us any closer to understanding it?� Jeff Lepler from Michigan has the following question:



�Q: Are we any closer to understanding the root cause of gravity between objects with mass? Can we use our newly discovered knowledge of the Higgs boson or gravitational waves to

Experimental Search for Quantum Gravity 2016

Research in quantum gravity is quite a challenge since we neither have a theory nor data. But some of us like a challenge.
So far, most effort in the field has gone into using requirements of mathematical consistency to construct a theory. It is impossible of course to construct a theory based on mathematical consistency alone, because we can never prove our assumptions to be true. All we know is

I�ve read a lot of books recently

[Reading is to writing what eating is to...]

Dreams Of A Final Theory: The Scientist's Search for the Ultimate Laws of Nature
Steven Weinberg
Vintage, Reprint Edition (1994)

This book appeared when I was still in high school and I didn�t take note of it then. Later it seemed too out-of-date to bother, but meanwhile it�s almost become a historical document. Written with the pretty explicit aim

Sorry, the universe wasn�t made for you

Last month, game reviewers were all over No Man�s Sky, a new space adventure launched to much press attention. Unlike previous video games, this one calculates players� environments from scratch rather than revealing hand-crafted landscapes and creatures. The calculations populate No Man�s Sky�s virtual universe with about 1019 planets, all with different flora and fauna � at least that�s what

Dear Dr. B: How come we never hear of a force that the Higgs boson carries?

�Dear Dr. Hossenfelder,
First, I love your blog. You provide a great insight into the world of physics for us laymen. I have read in popular science books that the bosons are the �force carriers.� For example the photon carries the electromagnetic force, the gluon, the strong force, etc. How come we never hear of a force that the Higgs boson carries?Ramiro Rodriguez�
Dear Ramiro,

The short

What if the universe was like a pile of laundry?

What if the universe was like a pile of laundry?
Have one.
See this laundry pile? Looks just like our universe.
No?
Here, have another.
See it now? It�s got three dimensions and all.
But look again.
The shirts and towels, they�re really crinkled and interlocked two-dimensional surfaces.
Wait.
It�s one-dimensional yarn, knotted up tightly.
You ok?
Have another.
I see it clearly now. It�s

Away Note

I'll be in Stockholm next week for a program on Black Holes and Emergent Spacetime, so please be prepared for some service interruptions.

Real Life: Balance

Being a mom & running a business is HARD work. There aren't enough hours in a day to do both as well as I'd like. I admit it. There are days I wish I had my nanny even longer, but then I'd never spend time with my son. It's all about perfecting balance I guess.....& that, I am still working on. Today I looked down at my little guy & he was wearing this t-shirt I designed. Says "mom & dad are my heroes" .... It made me smile. ...that maybe he thought I was doing just great... That in his eyes, I was HIS HERO.  

It made all this hard work today...feel a little better.

Follow more on my instagram.

T-shirt from my shop -  Cocoa & Hearts

Hey Moms, Check out the new shop!

Hey everyone! I have been working on some new things theses days, my apologies that I am not on here as much. However, for those not following on social media, you can now see the new Kids shop I've launched!

The t-shirts are for KIDS (boys & girls) 10 styles in the launch collection! We just LAUNCHED today! Shop for your kiddos give them as gifts ...Check them out at Cocoa & Hearts & take advantage of our launch discount code.

-pic by sage and sparkle

The Philosophy of Modern Cosmology (srsly)

Model of Inflation.img src: umich.edu

I wrote my recent post on the �Unbearable Lightness of Philosophy� to introduce a paper summary, but it got somewhat out of hand. I don�t want to withhold the actual body of my summary though. The paper in question is


Scientific Realism and Primordial Cosmology
Feraz Azhar, Jeremy Butterfield
arXiv:1606.04071 [physics.hist-ph]
Before we start I have to

බලන්නකො යාළුවන්ට ණය දුන්නම වෙන දේ

මේක ලබාගත්තෙ  Funny Video Clips ආතල් විඩියෝ youtube නාලිකාවෙන්

Pia Bajpai unseen

The Unbearable Lightness of Philosophy

Philosophy isn�t useful for practicing physicists. On that, I am with Steven Weinberg and Lawrence Krauss who have expressed similar opinions. But I think it�s an unfortunate situation because physicists � especially those who work on the foundations of physics � could need help from philosophers.
Massimo Pigliucci, a Prof for Philosophy at CUNY-City College, has ingeniously addressed

ලස්සනද කියල බලන්නකො

Breast Milk Hand Expression Lesson

පියයුරු නිවැරදිව සම්භාහනය කිරීම සහ අමතර කිරි ඉවත් කිරීමේ ක්‍රම

අද වන විට ගොඩක් කාන්තාවන්ට ඇති වන ගැටළුවක් තමා පියයුරු පිළිකා ඇතිවීම. මේ සදහා විවිද හේතු බලපානව. නුසුදුසු රුපලාවන්‍ය ක්‍රම, ඉතා තද යට ඇදුම් නිතරම භාවිත කිරීම, අහාර පුරුදු, පවුල් සම්භවයෙන් පැමිණීම. පියයුරු පිළිකා යනු අනෙක් පිළිකා මෙන් නොව මුලින්ම සොයා ගත්තොත් සුව කරගත හැකි රෝගයකි. නමුත් එහිදී ඔබට ඔබගේ පියයුරු ඉවත් කිරීමට බොහෝවිට සිදුවනු ඇත. ඉතින් හොදම දේ තමා පියයුරු පිළිකා වැළදීමෙන් වැලකි සිටීමටය. ඒ සදහා එක් අවධානය යොමු කල යුතු ක්‍රමයක් තමා අද දැනුවත් කරන්න යන්නෙ.

පියයුරු පිළිකා ඇතිවීමට තවත් එක් හේතුවක් තමා ක්ෂීර ග්‍රන්ථි වල කිරි කැටි ගැසීම. සාමාන්‍යයෙන් ක්ෂීර ග්‍රන්ථි වල කිරි ඉතුරු වෙනව. මේම කිරි කැටි ගැසුණු පසු ඉවත් කිරීම ඉතා අපහසු ක්‍රියාවකි. දරුවාට හැකියාවක් නැහැ සියලුම කිරි පානය කිරීමට. ඉතින් ඔබට සිදු වනව එම  කිරි ඉවත් කිරීමට දරුවාට කිරි දුන් පසු. නැතහොත් එම කිරි කැටි ගැසී වේදනාවක් ඇතිවීමටත් පසු කලක පියයුරු පිළිකා ඇතිවීමටත් ඇති අවදානමත් වැඩි වනව. ඉතින් මේ සදහා නිවැරදිව කිරි ඉවත් කරන විදිය ගැන පහත ඇති වීඩියෝ දෙක හරහා ඔබට ඉගෙන ගත හැක. පළමු විඩියොවෙන් ඔබට පෙන්වන්නෙ කෙසේද සම්භාහනය මගින් පියයුරු උත්තේජනය කරගන්නෙ කෙසේද කියා. දෙවැනි විඩියොවෙන් ක්ෂිරය ඉවත් කරගන්න ආකාරය ඉදිරිපත් කරයි. මෙය අධ්‍යාපනික වීඩියෝ පාඩමක් වුවත් අවුරුදු 18 ට අඩු අය නැරඹීමෙන් වලකින්න කියා ඉල්ලනව.

වීඩියෝ නැරඹීමට මෙතැනින් පිවිසෙන්න

The LHC �nightmare scenario� has come true.

The recently deceased diphoton
bump. Img Src: Matt Strassler.

I finished high school in 1995. It was the year the top quark was discovered, a prediction dating back to 1973. As I read the articles in the news, I was fascinated by the mathematics that allowed physicists to reconstruct the structure of elementary matter. It wouldn�t have been difficult to predict in 1995 that I�d go on to make a

මැණික් fb එකේදී කරපු වැඩේ බලන්නකො

මැණික් විජේවර්ධන fb එකේ කරපු දේවල් 

යාලුවන්ටත් බලන්න share කරන්න 

Math blind

[Img Src: LifeScience]

Why must school children suffer through so much math which they will never need in their life? That�s one of these questions which I see opinion pieces about every couple of months. Most of them go back to a person by name Andrew Hacker whose complaint is that:

�Every other subject is about something. Poetry is about something. Even most modern art is about something.

Can we please agree what we mean by �Big Bang�?

Can you answer the following question?

At the Big Bang the observable universe had the size of:


A) A point (no size).
B) A grapefruit.
C) 168 meters.

The right answer would be �all of the above.� And that�s not because I can�t tell a point from a grapefruit, it�s because physicists can�t agree what they mean by Big Bang!
For someone in quantum gravity, the Big Bang is the initial

Can black holes tunnel to white holes?

Tl;dr: Yes, but it�s unlikely.

If black holes attract your attention, white holes might blow your mind.
A white hole is a time-reversed black hole, an anti-collapse. While a black hole contains a region from which nothing can escape, a white hole contains a region to which nothing can fall in. Since the time-reversal of a solution of General Relativity is another solution, we know that white

Pulsars could probe black hole horizons

The first antenna of MeerKAT,
a SKA precursor in South Africa.
[Image Source.]
It�s hard to see black holes � after all, their defining feature is that they swallow light. But it�s also hard to discourage scientists from trying to shed light on mysteries. In a recent paper, a group of researchers from Long Island University and Virginia Tech have proposed a new way to probe the near-horizon

Cocoa & Hearts News

Hey everyone! Hope this Monday is going good for you! -  I thought I'd pop in & update you on this NEW Kids t-shirt line we are putting together!!  We are actually re-doing our entire Cocoa & Hearts website + re-branding it.  The Cocoa & Hearts site will no longer be paintings, but you can go to Made By Girl if you're looking to have me paint an original painting for you. Sound good?

The new Cocoa & Hearts logo will look like this (below) & we will be seeking out a few K-I-D-S brand ambassadors. That means.... we will send them a few t-shirts in exchange for some cool pics on social media, tagging us & letting others know where to find the line!  The kids will be carefully selected based on your social media account, follower count etc.  Excited to introduce this to all of you! I know this is a different route and I may have many people un-follow me or stop reading the blog all together...because you you preferred to see home decor....& that's ok. When I first started Made By Girl, I had only 7 followers, so I understand what it's like to be at ZERO pretty much (if I have to be).  BUT, I really hope to have your support through this in any way, especially all YOU moms!

As I mentioned before - we'll be launching about 8-10 t-shirt designs to start with. Can't wait to see which is your favorite.  Sizes will range from 18 Months old - 4 years of age. Please don't forget, if you'd like be notified of the launch date - SIGN UP to our mailer at Cocoa & Hearts.  XO

-post by jen ramos

The World Dangerous 25 Selfies EVER

ජංගම දුරකතනයේ සහ කැමරාවේ විදුවුණු සීග්‍ර දියුණුවත් සමඟ මිනිසුන්ගේ ක්‍රියාකාරකම් පවා වෙනස් වී තිබෙනව. ඉතින් වර්තමානයේ එවැනි ලෙස ඇති වුනු දෙයක් ලෙස selfie චායාරුප නැතහොත් තමන් විසින් තමන්ව චයරුපයට නගන චායාරුප හැදින්විය හැකිය. මෙම සම්ප්‍රදායය මිනිසුන් අතර බෙහෙවින් ප්‍රසිද්ධ වන්න හේතුව ජංගම දුරකථන වල සීග්‍ර දියුණුවයි. කෙසේ නමුත් මෙය කොතරම් පිස්සුවක් වෙලා තිබෙනවාද කිවුවොත් selfie චායාරුප  මිනිසුන් තැනක් නොතැනක් නොබලා ගන්න උත්සහ කරනව. ඉතින් මෙහි තිබෙන්නෙ එවැනි ලෙසම ලබාගත් ඉතාම ලොව ඉතාම භයානක selfie 10 යි. ඔයාලත් බලන්නකො මේ වගේ දේවල් නම් කරන්න උත්සහ කරන්නවත් එපා ඔයාල . මේවගේ අමුතු අමුතු වීඩියෝ ලිපි ඔබට අපි ඉදිරියේත් ලබා දෙන්නම්කො. ඉතින් එතකන් අනංමනං ලෝකය සමඟ රැදී ඉන්න. 

Why the LHC is such a disappointment: A delusion by name �naturalness�

Naturalness, according to physicists.

Before the LHC turned on, theoretical physicists had high hopes the collisions would reveal new physics besides the Higgs. The chances of that happening get smaller by the day. The possibility still exists, but the absence of new physics so far has already taught us an important lesson: Nature isn�t natural. At least not according to theoretical physicists