A$AP Ferg
A$AP Ferg feat. Nicki Minaj Lyrics


We have lyrics for 'A$AP Ferg' by these artists:


Metro Boomin & NAV If Young Metro don't trust you, I'm gon' shoot you Tell…
Metro Boomin NAV Lil Uzi Vert If Young Metro don't trust you, I'm gon' shoot you Tell…
NAV If Young Metro don't trust you, I'm gon' shoot you Tell…
Nav & Lil Uzi Vert If Young Metro don't trust you, I'm gon' shoot you Tell…
NAV & Metro Boomin If Young Metro don't trust you, I'm gon' shoot you Tell…
Nav & Metro Boomin [feat. Lil Uzi Vert] If Young Metro don't trust you, I'm gon' shoot you Tell…
NAV / Metro Boomin If Young Metro don't trust you, I'm gon' shoot you Tell…
NAV Metro Boomin If Young Metro don't trust you, I'm gon' shoot you Tell…
NAV Metro Boomin Lil Uzi Vert If Young Metro don't trust you, I'm gon' shoot you Tell…
NAV; Metro Boomin If Young Metro don't trust you, I'm gon' shoot you Tell…


We have lyrics for these tracks by A$AP Ferg feat. Nicki Minaj:


Nicki Minaj I went out to Ohio, there was like a mini…
Plain Jane Young Money Ayo Ferg Yeah Ride with the mob, Alhamdulillah …
Plain Jane ft. Nicki Minaj Young Money Ayo Ferg Yeah Ride with the mob, Alhamdulillah …
Plain Jane REMIX Young Money Ayo Ferg Yeah Ride with the mob, Alhamdulillah …


We have lyrics for these tracks by A$AP Ferg:


402 Damn who knocking on the fucking door like that, shit I…
4:02 Damn who knocking on the fucking door like that, shit I…
Aww Yeah Yeah Sh Quiet hater I'm a Traplord again The Traplord, Hood…
Back Hurt I'm a lucky bastard, my car like Dukes of Hazzard I…
Beautiful People We got our ways, but ain't we human beings too? If…
Butt Naked Hoot, hoot (damn) I know that you feel the adrenaline I…
Coach Cartier Yeah, rainbow shot my wrist Rainbow shot my wrist Rainbow sh…
Cocaine Castle Everybody going to this cocaine castle You'll probably see y…
Dennis Rodman Yeah, please Woo, woo, woo Ayy, the party is poppin' (ayy) …
Didn't Wanna Do That They told me West got robbed (Damn) Where the fuck them…
Doe-Active They mad, they mad They mad, why they mad? They mad, and…
Dreams Fairytales Fantasies (Mm) yeah, ah I call you gata, 'cause you's a wild…
Dump Dump Her hands all on my fade, bitch pop that ass…
East Coast Yeah, I need everybody to open this shit up Everybody open…
East Coast REMIX Run it up, run it up, run it up, run…
F**k Out My Face Get the fuck out of my face Get the fuck out…
Fergivicious Yeah, a lot of you people look at me like "Who…




Fergsomnia I can't stop, I'm ambitious Fucking hunnids of bitches Put a…
Floor Seats Coo, coo, damn Floor seats for the Knicks Couple models gon…
Fuck Out My Face Get the fuck out of my face Get the fuck out…
Grandma All I ever wanted was a minute with my grandma I…
Green Juice Yeah, this for Harlem Silk City Vado, what up? Nellz, what u…
Harlem Harlem Harlem Harlem Harlem Causing ruckus in the Rucker I'…
Hood Pope Oh let me sing my song, if you feel this…
Hummer Limo yeah See me with my VV teeth, yeah (Ooh) I got LV…
Hungry Ham See this is Harlem, these our streets Hungry Ham, that's all…
I Love You We could fly to Puerto Rico and fight a mosquito Or…
Intermission What's good? This Dame Lillard, AKA Dame D.O.L.L.A., checkin…
Ja Rule [Verse 1: A$AP Ferg] [Hook: A$AP Ferg] Sing like I'm Ja R…
Jet Lag yeah, uh yeah (yeah) Sit leaned back (woo), got a lot of…
Let It Bang Grandma hid that hammer in her mattress from my uncle He…
Let It Go Trap Lord season begins, now repent your sins This Yamborghi…
Let You Go She questioned my lyrics My love for your music is bitterswe…
Lord I ain't never had shit Not a pot to piss, window…
Mad Man Whatchu know man it's A$AP, nigga It's A$AP nigga stop all…
Make A Scene Neighbourhood is rough And livin' ain't easy Streets is so…
Move Ya Hips It's that time again (Frankie motherfuckin' P) Fergie, come …
Murda Something Murda, Murda Murda, Murda Some say I'm possessed, that's wh…
Nandos Nowadays shit is crazy out here man Gotta protect yourself Y…
Nasty Ay, ya, ya, ya, ya, ya (yeah) Ay, ya, ya, ya,…
New Level Yeah, yeah A$AP Turn my vocals up a little bit more please,…
New Level REMIX I'm on a new level, I'm on a new level I'm…
No Ceilings (AXL) Yeah, uh Ain't playin' with niggas (yeah) 'Cause we a…
Not The Boy Ay, ay, ay (Set it on fire Let it go up in…
Now Oh my gosh, thought I was stronger Said I wouldn't be…
Olympian Yeah I run run run I'm runnin' to the money now Yeah…
One Night Savage (Perfect) When you get the money, all your bitches be…
Perfume Trap Lord in my belly, free my nigga Really Elijah smoking…
Plain Jane Ride with the mob Alhamdulallah Check in with me, and do ya…
Psycho Ah, yeah Ah, it was all at the park Colonial Liquor was…
Pups Where my dawgs at? (We right here, dawg) Where my dawgs…
Rebirth If I die before I wake At least I lived life…
Ride Ayy, I just wanna ride with you Ayy, I just wanna…
Rubber Band Man You already know what it is, Hood Pope (Killa!) Dipset (A$AP…
Shabba Short nigga but my dick tall What I told your bitch…
Strive You can be you today You can be you tonight Know you're…
Swipe Life Picture me in the club, all the models around, bitch Tip…
Talk It [Verse 1] All I ever wanted was a Clams Casino beat To…
Tango Makin' money for the long term Off these words Yeah, yeah gi…
TATTED ANGEL Yeah, shit I'm going through a lot Art Basel night out…
The Mattress Mattress, mattress, mattress (uh) Mattress, mattress, mattre…
This Side On this side kids do drugs On this side kids gang…
Thought I Was Dead Yeah, uh Uh My ex just called, she cryin' She bangin' my li…
Trap And A Dream Yeah, yeah Pray to the trap Pray for the trap Send them nig…
Uzi Gang If the bitch ain't on me, she on Ferg Ask them…
Value Yeah ho (yeah) Yeah (uh) Yeah ho (yeah) Yeah (uh) Yeah (oh) …
Verified At 7 AM I wake up, hit the green I hit…
Wam Yeah, yeah Ooh, ooh, go Man, I got all the flavor bitches…
What Do You Do What do you want Cut my grass low See the snakes all…
Wigs Wigs on the floor Wigs, wigs on the floor Ayy, yeah Ayy, ayy…
Work Yeah, straight off the plane Drop in the flame A lot of…
Work Remix I gotta close the window before I record Cause New York…
Work Remix feat. A$AP Rocky French Montana Trinidad James & ScHoolboy Q I gotta close the window before I record Cause New York…
World Is Mine Yeah (Better get the fuck out my face) You always tellin' me…
Yammy Gang All of my niggas gon' ride, all of my niggas…


We have lyrics for these tracks by Nicki Minaj:


#Twerkit Big man! When I talk, hear weh yuh fi do? Shut…
'Roman In Moscow' I’m big willie, no bike gear I told you bitches last…
02 I Lied Oh oh oh Oh oh oh Oh oh oh Oh oh oh I lied,…
1234 (just nicki's verse) It's Barbie Bitch! I'm the Barbie…
2 Lit 2 Late Interlude I said I'm cool on it, baby, yeah, I'm straight He…
2012 Oh Jay Sean (Jay Sean, Jay Sean) 2-0-1-2 (Nicki Minaj, Nicki…
23. Born Stunnas (Beat Billionaire) Born stunna (Maybach Music) Huh (yeah), I…
3. Kill The Dj Aphelliates nigga, pay attention Hey, hey, hey You know it …
40 Bars Fitted down and I'm reddii 2 play When yo album gon'…
5 star Tunechi Barbie Young Money I been smokin' gas, killin' bitc…
5star This, this is another banger Turn it the fuck up This is…
64. I Aint Thru Ohh-whoa, yeah, yeah, yeah, yeah (Young Money) Oh, yeah See…
67. I Don't Give A Wake up, ex-wife This is your life Children, on your own Tur…
7. Bottoms Up Yeah Oh oh oh oh (This mister steal your girl) Oh oh…
70. I Luv Dem Strippers (Marvel) Uh, yeah 2 Chainz Let's play big bank take little …
74. Take It To The Head Another one DJ Khaled Working all winter Shining all summer…
76. Take It Off Them girls like them bad boys Them girls like them bad…
83. Best I Ever Had Yo it's The Aphelliates nigga, pay attention (yeah) Nicki Mi…
89. Beauty And A Beat Yeah Young Money Nicki Minaj, Justin Show you off, tonight …
All I Do Is Win D-J Khaled Hey, yeah (we the best) All I do is win…
All I Do Is Win [feat. T-Pain Diddy DJ Khaled Rick Ross Busta Rhymes Fabolous Jadakiss Fat Joe & Sw D-J Khaled Hey, yeah (we the best) All I do is win…
All Things Go Yo, I had to reinvent, I put the V in…
Anaconda My anaconda don't, my anaconda don't My anaconda don't want …
Animales Dejaste en mi cama tu aroma y sudor No olvido el…
Arctic Tundra Bad bitches run the world, let me make it clear When…
are you gone alREADY What you doing, Papa? Hi, no, uh-uh Say, "Hi" (hi) Don't yo…
Attack It's Barbie bitches We got Tom Tom's over here bigger than…
Autobiography [Nicki Speaking] This is the autobiography of Nicki Maraj …
Automatic I can't control the way I'm movin my hips Bet you…
B.A.D Patty, I see you too This what y'all be wanting? This what…
Baddest Bitch Uh-huh (Sycamore) Now every club promoter wanna bid like au…
Bahm Bahm (Jess, your beat on the radio) Ayo There I go again kickin'…
Barbiana ft. Cardi B Bust down, Barbiana, bust down, Barbiana Bust down and pick …
Barbie Dangerous (28Shit) Ayo Barbie dangerous Weak bitches don't endanger u…
Barbie Dreams Uh, mh, k'yeah R.I.P. to B.I.G Classic shit I'm looking for…
Barbie Girl Whats a barbie to do i mean it's like, it's…
Barbie Tingz Dem-dem-dem-dem dem-dem Dem-dem-dem-dem Dem-dem-dem-dem dem-…
Barbie World I'm always yours (stop playin' with 'em, RIOT) Ooh whoa An…
Beam Me Up Scotty You know they say who, who is Nicki Minaj and…
Beautiful Nightmare Turn the lights on! Every night I rush to my bed With…
Beautiful Sinner South Africa is where I come from Get me my banjo,…
Beauty and a Beat Yeah Young Money Nicki Minaj, Justin Show you off, tonight …
BED Got a bed Wit' your name on it Wit' your name on…
Bed Of Lies Do you ever think of me when you lie? Lie down…
BedRock I-I-I-I can make your bed rock (Young Money) I-I-I-I can mak…
BedRock ft. Young Money I-I-I I can make your bed rock (Young Money) I-I-I I…
Beef Stew Just when they thought I was done for the summer Came…
Beep Beep (Murda on the beat so it's not nice) Ayo I drop a…
Bees in a trap Yo, man, man, uh Bitches ain't shit and they ain't saying…
Beez In The Trap Ft 2 Chainz Yo, man, man, uhh Bitches ain't shit and they ain't saying…
Best It was back in '07 did a couple of tapes Did…
Best I Ever Had Yo it's The Aphelliates nigga, pay attention (yeah) Nicki Mi…
Big Daddy You hear that right there? That sound like, but that three…
Big Difference (Monsta's gon' tear it up) Like my hunnids blue (blue) Bad …
BiG FoOt (Been trill, been doin' it, been at it) Your flow is…
Black Barbies Mike Will Made It Nigga Sremm Life Black Barbies in the city…
Blazin Hey, hey, yeah Oh, oh (hey, hey, hey, hey) Oh (ooh) I fly,…
Blazin ) I fly, I fly high, I'm blazing, I'm blazing, feels like…
Blazin' I fly, I fly high, I'm blazin', I'm blazin', feels like…
Blessings Blessings, blessings on blessings On God, God, God Woo (Sad …
Blow Ya Mind She said her name was Nicki She came to play, and…
bom bidi bom I was wrong and you were right If I was yours…
Born To Be Wild [Sean kingston] I was just a player in the game of…
Boss Ass Bitch I'm a boss ass bitch Bitch, bitch, bitch, bitch, bitch, bitc…
Boss Ass Bitch Remix ft. PTAF I'm a boss ass Bitch, bitch, bitch, bitch, bitch, bitch, bit…
Bottom's Up Yeah Oh oh oh oh (This mister steal your girl) Oh oh…
Bottoms Up Yeah, come here, ooh This mister steal your girl This mist…
Bottoms Up ft. trey songs Yeah Oh oh oh oh (This mister steal your girl) Oh oh…
Bought Out The Bar Ah ha, Harlem it's Barbie bitch! Ha DJ Webstar Nah I’m good…
Break Up When I kiss you so good (Mario) Why would you wanna…
Bring It Back Yo, listen all y'all muh'fuckas Y'all know who Nicki Maraj i…
Brraaattt (Nicki Minaj) Tell These Bi***es That iM Not The One, Some…
Brraattt uck x8 Take that with you on the way down Buck x8 Up…
Bussin Yeah, my connect just now sent my wrist back Tell these…
Bust Down Barbiana Bust down, Barbiana, bust down, Barbiana Bust down and pick …
Buy a Heart (You should say it right now) Anybody wanna buy a heart? An…
Can Anybody Hear Me [ VERSE ] I push, p-p-push it, I p-p-push it like…
Can't Stop Yessir, this shit right here's called can't stop, won't stop…
Can't Stop Won't Stop Goodmorning New York, Good Afternoon New Orleans, Goodnight …
Can't Stop Won't Stop Feat. Lil' Wayne Yessir, this shit right here's called can't stop, won't stop…
Catch Me Extracurricular, parallel and then I am perpendicular Hit …
Champion This a celebration, this is levitation Look at how you winni…
Changed It I did it for everybody out here on they own I…
Check It Out Stepped in the party like my name was "that bitch" All…
Chi-Raq Mmh uh Ain't yellin' cut when it's shootin' time Sign up, i…
Chun Li Ayy, yo Look like I'm goin' for a swim Dunked on 'em,…
Chun Swae Fall off in the spot All you niggas do is run…
Chun-Li Ayy, yo Look like I'm goin' for a swim Dunked on 'em,…
Clappers Don't mind me baby, heh We takin' over summer Young Gifted, …
Click Clack A lot of rap niggas be trynna play hard I was…
Coco Chanel (Whole lotta gang shit) Oh, uh, ugh, ay yo Chun, uh Ay…
Come on a Cone Bitches ain't serious, man, these bitches delirious All thes…
Come See About Me Come, come see what I've been up to Come, come see…
Cowgirl Just wanna get drunk tonight And I'ma ride him cowgirl, cowg…
Crocodile Teeth Mmh, mmh Ayo First thing I'ma do when I pop out is…
Cuchi Shop [Talking:] Welcome to Star Box Yeah shawty I'm tryna get m…
Cupid's Got A Gun [shanell] You watched me fall Stood over me as I hit the…
Curious George .Nicki Minaj. Yo why these bitches in the game gettin' seri…
Dance Ass ass ass ass ass Ass ass ass ass ass Ass ass…
Dang A Lang Excuse me, can I see your danglin', brother? I mean, you…
dead wrong You be yellin boom boom when ya really poom poom You…
Dear Old Nicki Mmh-ohh Mmh Yo Maybe you died 'cause everybody ask me where…
Dear Old Nicki Lyrics Maybe you died 'cause everybody ask me where you at I…
Did It On Shitted on 'em Man, I just shitted on 'em Shitted on 'em Put…
Did It On ‘Em Shitted on 'em, Man I just shitted on 'em Shitted on 'em, Pu…
Did It On'em Shitted on 'em Man, I just shitted on 'em Shitted on 'em Put…
Did It On’em ) Shitted on 'em, Man I just shitted on 'em Shitted on 'em, Pu…
Dilly Dally [Talking:] Nicki Minaj, Dirty Money, I don't think y'all un…
Dirty I don't wanna sound mad Though! I don't wanna sound mad! I…
Dirty Dub Carter called, lemme get the car key You don't want it…
Dirty Money I don't wanna sound mad Though! I don't wanna sound mad! I…
do we have a problem I just told Pee, "This really niggas' worst nightmare, man T…
Do You Mind Another one We The Best Music! Yo, he ain't messing with no…
Doin' It Well (Go ahead) See you can't just do it (Go ahead) You gotta do…
Don't Hurt Me Tryna get up in my head, now that's a headache I…
Dopeman Dopeman please can I have another hit Dopeman Dopeman Dopem…
Dreams As I sit back, relax, crack jokes for minute I think…
Dreams '07 As I sit back, relax, crack jokes for a minute…
Dungeon Party SASnicki M Went out to London partied at the dungeon Went o…
Dutty Dutty Hey yo Sean, you Mister Kingston Dutty dutty dutty love lov…
Ease Up [Hook] Where my niggas that getting they G’s up (G’s up) I…
Easy [Verse: Gucci Mane] Hot dammit it's a miracle, Please adj…
Eazy [Verse: Gucci Mane] Hot dammit it's a miracle, Please adjust…
Encore '07 [Intro] Thank you Thank you for comin' out tonight Ladies…
Envy Nigga holla at your boy See I think y'all see the…
Everybody Mm Ain't gang if you let shit slide Ain't bad if you…
Everywhere We Go Lil' Kim stay on y'all brains Nothin' ass broads tryin' to…
Fallin 4 U (ATL Jacob, ATL Jacob) Ayo Told him shoot his shot like his…
Familia Father, father, unforgivable This is my house, you made it p…
Favorite I don't want no drama I just wanna be your diamond,…
Favorite Feat. Jeremih I don't want no drama I just wanna be your diamond,…
Feel Free [Nicki Minaj:] Hopped off the boat, I am such a immigrant …
Feel Free Feat. Ricky Blaze (Pay, pay, attention!) (Pay attention!) Shouts out Bogies, I…
Feeling Myself Yo B, they ready Let's go Feelin' myself, I'm feelin' mysel…
FEFE It's fuckin' TR3YWAY! It's King of New York, lookin' for the…
Finale What it do nigga This your nigga T-Streets bang bang In the…
Fire Burns Mmm, you shoulda left the other day You let me beg…
Fireball Willow, Willow Um, hello, can we get the party started, yeah…
Firm Biz Ya girl been hot since Corduroys Since quarter waters, and a…
Firm Biz 08 Nicki Minaj: Your girl been hot since corduroys Since quar…
Firm Biz Feat. Jadakiss Ya girl been hot since Corduroys Since quarter waters, and a…
Five Star Chick Tunechi Barbie Young Money I been smokin' gas, killin' bitc…
Five-O This, this is another banger Turn it the fuck up This is…
Five-O ft. Jae Millz [Chorus:] Where my straitjacket at... I'm a psycho Where t…
Five-O ft. Jae Millz %26 Gudda Gudda This, this is another banger Turn it the fuck up This is…
Five-O ft. Jae Millz & Gudda Gudda [Chorus:] Where my straitjacket at... I'm a psycho Where t…
Flawless Dum-da-de-da Do, do, do, do, do, do (Coming down, dripping c…
Fly I came to win, to fight To conquer, to thrive I came…
For The Money Write another song for the money My shawty say Write another…
Forward From Trini (Bas Beats) Yuh sih? Fully dunce Bruk a gyal bad like Nicki…
Four Door Aventador Plenty more for you, boy We in the funky four door,…
Fractions I fell back, I had a baby, you know I did…
Freaky Girl (feat. Lil Kim) [Talking:] Oh I Get It Oh Okay Niggas Tr…
Freaky Girl Feat. Gucci Mane She's alright That girl's alright with me Yeah Ayo (hey, hey…
Freedom They'll never thank me for opening doors But they ain't even…
Freestyle I don't want to sound mad though I don't want to…
FTCU Fuck this club up Fuck this, fuck this club up…

and many more tracks by Nicki Minaj.


The lyrics are frequently found in the comments by searching or by filtering for lyric videos
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Most interesting comment from YouTube:

@user-fu3qj6xd5x

[Chorus: A$AP Ferg]
Ride with the mob, Alhamdulillah
Check in with me and do your job
Ferg is the name, Ben Baller did the chain
Tourneau for the watch, presi Plain Jane

[Verse 1: A$AP Ferg]
Yamborghini chain, rest in peace to my superior
Hermès link could feed a village in Liberia
TMZ taking pictures, causin' mad hysteria
Momma see me on BET and started tearin' up
I'mma start killin' niggas, how you get that trife?
I attended Harlem picnics where you risked your life
Uncle used to skim work, sellin' nicks at night
I was only 8 years old, watching Nick at Nite
Uncle Psycho was in that bathroom buggin'!
Knife to his guts hope Daddy don't cut him
Suicidal thoughts brought to me with no advisory
He was pitchin' dummy, sellin' fiends mad ivory
Grandma had the arthritis in her hands, bad!
She was poppin' pills like rappers in society
I fuck yo bitch for the irony
I'll send Meechy at yo hoe if yo bitch keep eyein' me

[Chorus: A$AP Ferg]
Ride with the mob, Alhamdulillah
Check in with me and do your job
Ferg is the name, Ben Baller did the chain
Tourneau for the watch, presi Plain Jane
Ride with the mob, Alhamdulillah
Check in with me and do your job
Ferg is the name, Ben Baller did the chain
Tourneau for the watch, presi Plain Jane

[Post-Chorus: A$AP Ferg]
Suck a nigga dick or somethin' (Yeah)
Suck a nigga dick or somethin' (You already know, Harlem)
Suck a nigga dick or somethin' (Queens)
Suck a nigga dick or somethin' (Queens for the Kings of the Queens)

[Verse 2: Nicki Minaj]
Ayo, I'ma explain why you probably never see me
I push a Lamborghini, chocha magic like Houdini
My body shaped like Jeannie, booty dreamy, waist is teeny
Yes, I told him to get TIDAL so he stream me when he leave me
I go hard in the booth, Biggie vibes, gimme the loot
I’m a classy millionaire, bitches ain’t got the couth
C-O-U-T-H 'cause you can’t spell it either
If I call him then he comin' home running, Derek Jeter
Bitches must be eatin' ass because I swear they’re bottom feeders
Hoe, you know that you my son, I shoulda scrapped you as a fetus
All these bitches rockin' inches 'cause they followin' the leader
I should switch it up on hoes and rock a Afro like Lupita's
I don’t keep up with the Joneses but I do know Catherine Zeta
I’m with Candice, TT, Thembi, and Viola, mi amiga
Rap bitches they gotta check in with the Queen
I’m the Alpha, the Omega, everything in between, uh

[Chorus: Nicki Minaj]
Ride with Minaj, mmh Mashallah
Check in with me, then do your job
Queen is the name, Rafaello did the chain
This is Monse, patty Plain Jane
Ride with Minaj, mmh Mashallah
Check in with me, then do your job
Queen is the name, Rafaello did the chain
This is Monse, patty Plain Jane

[Post-Chorus: Nicki Minaj]
Eat a Barbie ass or somethin'
Eat a Barbie ass or somethin'
Eat a Barbie ass or somethin'
Eat a Barbie ass or somethin'



All comments from YouTube:

@rekarzaman

0:12 ferg : hamdullilah
2:40 nicki : mashallah
3:25 me :astaghfirullah

@utakatasama9155

😂😭😂😭😂😭😂😭😂😭😭😂😭😂

@hadih9081

🤣😫😫😫😂😂🤣🤣🤣

@sifremneydi8597

😂😂😂

@sovietunion1700

Freg?😂

@rekarzaman

Exotic Beats sorry 😅😂

129 More Replies...

@MBSD2007Owner

Phone : 1%
Me : plays this song
Phone : 2%

@shahnawaz-kz4sk

Funny tha ?

@Kenan_Guney

Dude, cmon. You can't create energy. To answer "why you can't create energy" you should first ask "what is energy?". It's not something you can see, touch or smell. It's not something you can measure directly, so you can say it doesn't really exist. It's a mathematical abstraction, some property. And the way this property is defined makes it conserved, under certain conditions.

Take classical mechanics. It's initially based on simple Newton's laws that came from observation (and some basic assumptions) and include some very physical and measurable things like positions, velocities, masses and forces. Newton did not use any notion of energy, he probably didn't even have an idea of energy in his model of physics. Energy is not needed there! Then people discovered that you can come up with a formula, a function (Lagrangian) that, combined with a certain principle (of stationary action) can lead to the same equations of motion as Newton's laws, and these equations are often more useful than Newton's for solving different problems in mechanics. It was just playing with equations, math, no significant new physics there. Still no energy in the picture here. Lagrangian is a function of positions and speeds of particles/objects, and the way this function looks depends on the system you describe. Then, still playing with equations, people realized than if Lagrangian function does not depend directly on time, we can make of it another function of positions and speeds, that would not change in time. It's called Hamiltonian and it's conserved just by construction, assuming your initial description of the system does not depend on time directly, only on positions and speeds. And the value of this function is what's known as energy. In many cases the formula can be split into part that only depends on speeds, it's called kinetic energy, and a part that depends on positions, it's called potential energy. In systems where all mentioned assumptions are true, you get just by construction this fact that total sum of kinetic and potential energy stays the same, it's conserved, which means "you can't create energy". You can't just because you defined energy as something that's conserved. In systems where Lagrangian depends on time, it's not conserved. What does it mean? Lagrangian not depending on time means your system behaves the same no matter when you do the experiment: morning or evening, March or October. If its description does not include time directly, just positions and speeds of its parts, it's time translation invariant and automatically gives you conservation of energy. If it does depend on time, for example experiment depends on external magnetic field that's growing, then there is no time translation symmetry, energy is not conserved. For example, our universe is expanding with acceleration and it's not time-translation symmetric as a whole, so total energy of the universe is not conserved, it's growing! You might have heard of "dark energy". It's spread out in space and as universe expands and gains more space it gains more of that dark energy.

Then comes quantum mechanics. There initially you also don't have a notion of energy, you don't need it. Each state of the system is represented by a vector in some complex vector space, and this state somehow evolves in time. You can imagine a function that takes initial state, a vector, and time (how long to evolve) and gives you another vector, the state it evolved to. This function is an operator in vector space (for each t, i.e. U(t)). Since for zero change in time there must be no change in vector, this operator must be 1 for zero t, and 1 + something small for small t. Turns out if we factor out some complex constant from that "something small" we get a new operator H that has a property of an observable (it’s Hermitian) and also lets us calculate time derivative of state vector. Turns out this operator H as an observable corresponds to a thing we called energy in classical mechanics. But really it's just a mathematical construction, closely tied to time derivative of state. And because time derivatives of other operators are expressed via time derivatives of states, they depend on this H and can be calculated via so called "commutator" with H. And since commutator of an operator with itself is always zero, this time derivative of H (its expectation, really) is also zero, which means expectation value of energy is conserved, which means "you can't create energy". Just by construction of the math of energy.

@zainababbas4258

@@Kenan_Guney uhm

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