Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
La Ecuación de Dios. La Búsqueda de Una Teoría del Todo / The God EquationLa bsqueda del santo grial de la ciencia por el reputado fsico terico Michio Kaku. Cuando Newton formul la ley de la gravedad, unific las reglas que rigen los cielos y la Tierra. Hoy el mayor desafo de la fsica es encontrar una sntesis de las dos grandes teoras, basadas en principios matemticos diferentes: la de la relatividad y la cuntica. Combinarlas sera el mayor logro de la ciencia, una profunda fusin de todas las fuerzas de la naturaleza en una
La búsqueda del santo grial de la ciencia por el reputado físico teórico Michio Kaku. Cuando Newton formuló la ley de la gravedad, unificó las reglas que rigen los cielos y la Tierra. Hoy el mayor desafío de la física es encontrar una síntesis de las dos grandes teorías, basadas en principios matemáticos diferentes: la de la relatividad y la cuántica. Combinarlas sería el mayor logro de la ciencia, una profunda fusión de todas las fuerzas de la naturaleza en una hermosa y magnífica ecuación que nos permitiría comprender los misterios más profundos del universo: ¿qué sucedió antes del Big Bang? ¿Qué hay al otro lado de un agujero negro? ¿Existen otros universos y otras dimensiones? ¿Es posible viajar en el tiempo? Con ese objetivo, y con su conocida capacidad para divulgar conceptos complejos en un lenguaje accesible y atrayente, Michio Kaku repasa la historia de la física hasta llegar a los debates actuales en torno a la búsqueda de esa teoría unificadora, la «ecuación de Dios». Una historia cautivadora y contada de manera magistral, en la que lo que está en juego es nada menos que nuestra concepción del universo. ENGLISH DESCRIPTION #1 NEW YORK TIMES BEST SELLERThe epic story of the greatest quest in all of science--the holy grail of physics that would explain the creation of the universe--from renowned theoretical physicist and author of The Future of the Mind and The Future of Humanity When Newton discovered the law of gravity, he unified the rules governing the heavens and the Earth. Since then, physicists have been placing new forces into ever-grander theories. But perhaps the ultimate challenge is achieving a monumental synthesis of the two remaining theories--relativity and the quantum theory. This would be the crowning achievement of science, a profound merging of all the forces of nature into one beautiful, magnificent equation to unlock the deepest mysteries in science: What happened before the Big Bang? What lies on the other side of a black hole? Are there other universes and dimensions? Is time travel possible? Why are we here? Kaku also explains the intense controversy swirling around this theory, with Nobel laureates taking opposite sides on this vital question. It is a captivating, gripping story; what's at stake is nothing less than our conception of the universe. Written with Kaku's trademark enthusiasm and clarity, this epic and engaging journey is the story of The God Equation.
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.6 ★★★★★
Based on 1491 reviews
Sort
Product Reviews
★★★★★ 3
Defective Battery
Style: 20V Pwr Drv Trimmer (LST522-CA)
The trimmer works fine. Luckily I have many batteries. The battery that came with it is defective and I can’t seems to just exchange the battery for a good one.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 28, 2026
★★★★★ 5
FAST. Powerful. Easy to use.
Size: 8" Edger New
WOW! I bought a new house a couple of months ago, and the landscaping company overlapped the edge of the driveway with the sod. I've bee trying to trim it back with my string trimmer, but the results were less than desirable.
I got my new edger today, and I am astonished at the results! ruler straight edging, 2 1/2" deep and 1/4" wide. PERFECT! . . . and the whole front yard took less than 10 minutes! The edger is very powerful - it easily cut through the sod, deep into the dirt underneath leaving a nice clean edge. My neighbor has a lawncare company, and he was watching me. He came over and said he was going to get one for his jobs, as it is much faster and easier to use.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 21, 2025
★★★★★ 5
Easy to edge with
Size: 8" Edger New
This works great to edge an overgrown area like sidewalk and driveway. Super effective and easy to use.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
★★★★★ 5
GREAT 80v edger (but Kobalt users beware)
Size: 8" Edger Gen1, Size: 8" Edger Gen1
This Greenworks 80v edger is fantastic. I was surprised at how sturdy and rigid the shaft is - much more so than the very much more expensive Stihl Brushcutter I used for years. I like the adjustability of the blade depth and the power is impressive. You will get more run time with higher amp batteries - I have both 2.0 and 2.5 amp batteries, but if you have multiple batteries and chargers (from acquiring multiple tools) you will never be waiting for a battery to charge.
If you have only purchased Greenworks tools, then you are golden. BUT HERE IS THE RUB IF YOU, LIKE ME, THOUGHT THEY WERE STRAIGHT-ACROSS COMPATIBLE WITH THE SAME LINE OF TOOLS THEY MANUFACTURED FOR LOWE'S UNDER THE KOBALT MONIKER AND BLUE COLOR, AS DIFFERENTIATED FROM THEIR STANDARD BRIGHT GREEN.
One of the reasons I went ahead and committed to buying the Kobalt line of 80v yard tools was because Greenworks made them and I figured that it would be a long-lasting and stable design platform, being the same 80v system across two different brands. Then Lowe's dropped the 80v line. I was able to get a few more of their tools for great clearance prices and looked forward to switching over to the complete line of Greenworks 80v tools. was very happy to be able to order their edger because it's the exact same power system - just that all of my gear is Kobalt blue.
AND HERE IS THE DEAL WITH THAT:
They are different. The Kobalt 80v battery will not fit/slide into the Greenworks 80v battery compartment/housing (*as manufactured). - I guess I shouldn't have been surprised - and it could have been Lowe's that required that the stuff made for them specifically would be incompatible. But since it's the same power system, I wondered what the difference was and if I could work-around their obstructionist corporate bs. What I discovered was that the battery compartment on the tools have two long molded channel-guides (male) that match the two long molded (female) channels in the batteries. The vertical placement of the bottom 'rail' in the tool/compartment is positioned in a slightly different spot between the Kobalt and Greenworks 'brands'. But this actually works, because I just used a hand chisel and removed the 'bottom' rail from the Greenworks tool/edger. WA-LA - EUREKA!!! It worked great! It's a great fit, the top rail is more than enough to hold the battery stably in position and the 'lock' mechanism functions perfectly!
I am looking forward to buying more tools in the Greenworks 80 volt line without having to replace all of the Kobalt tools I already paid for AND ESPECIALLY the rediculously expensive batteries...
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 29, 2021
★★★★★ 4
Great product that makes edging very fast
Size: 8" Edger New
Edging was quite a job because I had to do it with a hand tool. I have quite a few Greenwork tools, so I decided to purchase the edger. It works great and I am in general happy with it. The three downsides for me are that tool is quite heavy when it also has the battery in it, that the metal blade decreases in size rapidly because of the friction when edging near concrete, and that the wheel is in such a position that I have to bend substantially while the blade does not edge deep enough so that I have to lean the tool on the metal strip at the bottom of the tool.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on August 17, 2025