hold

Definitions

  • Holding a Large Board in Vise for Planing
    Holding a Large Board in Vise for Planing
  • WordNet 3.6
    • v hold keep from exhaling or expelling "hold your breath"
    • v hold remain committed to "I hold to these ideas"
    • v hold assert or affirm "Rousseau's philosophy holds that people are inherently good"
    • v hold keep in mind or convey as a conviction or view "take for granted","view as important","hold these truths to be self-evident","I hold him personally responsible"
    • v hold hold the attention of "The soprano held the audience","This story held our interest","She can hold an audience spellbound"
    • v hold be in accord; be in agreement "We agreed on the terms of the settlement","I can't agree with you!","I hold with those who say life is sacred","Both philosophers concord on this point"
    • v hold declare to be "She was declared incompetent","judge held that the defendant was innocent"
    • v hold bind by an obligation; cause to be indebted "He's held by a contract","I'll hold you by your promise"
    • v hold protect against a challenge or attack "Hold that position behind the trees!","Hold the bridge against the enemy's attacks"
    • v hold aim, point, or direct "Hold the fire extinguisher directly on the flames"
    • v hold drink alcohol without showing ill effects "He can hold his liquor","he had drunk more than he could carry"
    • v hold have or hold in one's hands or grip "Hold this bowl for a moment, please","A crazy idea took hold of him"
    • v hold be the physical support of; carry the weight of "The beam holds up the roof","He supported me with one hand while I balanced on the beam","What's holding that mirror?"
    • v hold to close within bounds, limit or hold back from movement "This holds the local until the express passengers change trains","About a dozen animals were held inside the stockade","The illegal immigrants were held at a detention center","The terrorists held the journalists for ransom"
    • v hold cover as for protection against noise or smell "She held her ears when the jackhammer started to operate","hold one's nose"
    • v hold support or hold in a certain manner "She holds her head high","He carried himself upright"
    • v hold organize or be responsible for "hold a reception","have, throw, or make a party","give a course"
    • v hold maintain (a theory, thoughts, or feelings) "bear a grudge","entertain interesting notions","harbor a resentment"
    • v hold cause to stop "Halt the engines","Arrest the progress","halt the presses"
    • v hold have or possess, either in a concrete or an abstract sense "She has $1,000 in the bank","He has got two beautiful daughters","She holds a Master's degree from Harvard"
    • v hold secure and keep for possible future use or application "The landlord retained the security deposit","I reserve the right to disagree"
    • v hold have rightfully; of rights, titles, and offices "She bears the title of Duchess","He held the governorship for almost a decade"
    • v hold take and maintain control over, often by violent means "The dissatisfied students held the President's office for almost a week"
    • v hold keep from departing "Hold the taxi","Hold the horse"
    • v hold arrange for and reserve (something for someone else) in advance "reserve me a seat on a flight","The agent booked tickets to the show for the whole family","please hold a table at Maxim's"
    • v hold lessen the intensity of; temper; hold in restraint; hold or keep within limits "moderate your alcohol intake","hold your tongue","hold your temper","control your anger"
    • v hold stop dealing with "hold all calls to the President's office while he is in a meeting"
    • v hold be valid, applicable, or true "This theory still holds"
    • v hold be pertinent or relevant or applicable "The same laws apply to you!","This theory holds for all irrational numbers","The same rules go for everyone"
    • v hold keep in a certain state, position, or activity; e.g., "keep clean" "hold in place","She always held herself as a lady","The students keep me on my toes"
    • v hold remain in a certain state, position, or condition "The weather held","They held on the road and kept marching"
    • v hold contain or hold; have within "The jar carries wine","The canteen holds fresh water","This can contains water"
    • v hold be capable of holding or containing "This box won't take all the items","The flask holds one gallon"
    • v hold resist or confront with resistance "The politician defied public opinion","The new material withstands even the greatest wear and tear","The bridge held"
    • v hold have room for; hold without crowding "This hotel can accommodate 250 guests","The theater admits 300 people","The auditorium can't hold more than 500 people"
    • v hold have as a major characteristic "The novel holds many surprises","The book holds in store much valuable advise"
    • n hold the act of grasping "he released his clasp on my arm","he has a strong grip for an old man","she kept a firm hold on the railing"
    • n hold the space in a ship or aircraft for storing cargo
    • n hold the appendage to an object that is designed to be held in order to use or move it "he grabbed the hammer by the handle","it was an old briefcase but it still had a good grip"
    • n hold a cell in a jail or prison
    • n hold a stronghold
    • n hold power by which something or someone is affected or dominated "he has a hold over them"
    • n hold understanding of the nature or meaning or quality or magnitude of something "he has a good grasp of accounting practices"
    • n hold a state of being confined (usually for a short time) "his detention was politically motivated","the prisoner is on hold","he is in the custody of police"
    • n hold time during which some action is awaited "instant replay caused too long a delay","he ordered a hold in the action"
    • ***

Additional illustrations & photos:

Charlie holding the broom that saved him Charlie holding the broom that saved him
A squirrel holding a partially eaten nut A squirrel holding a partially eaten nut
Three children holding firewood, in front of the fireplace with a cat Three children holding firewood, in front of the fireplace with a cat
Stephen holding a rose in his mouth Stephen holding a rose in his mouth
Geirald holds out the head of the giant to the king Geirald holds out the head of the giant to the king
The princess, holding a sword, stands over the sleeping snake The princess, holding a sword, stands over the sleeping snake
Hold On! Hold On Hold On! Hold On
Hold Her Down, Tom Hold Her Down, Tom

Webster's Revised Unabridged Dictionary
  • Interesting fact: Actress Meryl Streep holds the record for the most Oscar nominated actress, with a record of 13 nominations
    • Hold (Mus) A character placed over or under a note or rest, and indicating that it is to be prolonged; -- called also pause, and corona.
    • Hold A place of confinement; a prison; confinement; custody; guard. "They . . . put them in hold unto the next day.""King Richard, he is in the mighty hold Of Bolingbroke."
    • Hold A place of security; a fortified place; a fort; a castle; -- often called a stronghold. "New comers in an ancient hold"
    • Hold Binding power and influence. "Fear . . . by which God and his laws take the surest hold of ."
    • v. i Hold In general, to keep one's self in a given position or condition; to remain fixed. Hence:
    • Hold Not to fail or be found wanting; to continue; to last; to endure a test or trial; to abide; to persist.
    • Hold Not to fall away, desert, or prove recreant; to remain attached; to cleave; -- often with with to, or for.
    • Hold Not to give way; not to part or become separated; to remain unbroken or unsubdued.
    • Hold Not to move; to halt; to stop; -- mostly in the imperative.
    • Hold Something that may be grasped; means of support. "If a man be upon an high place without rails or good hold , he is ready to fall."
    • Hold The act of holding, as in or with the hands or arms; the manner of holding, whether firm or loose; seizure; grasp; clasp; grip; possession; -- often used with the verbs take and lay. "Ne have I not twelve pence within mine hold .""Thou should'st lay hold upon him.""My soul took hold on thee.""Take fast hold of instruction."
    • Hold The authority or ground to take or keep; claim. "The law hath yet another hold on you."
    • n Hold hōld (Naut) The whole interior portion of a vessel below the lower deck, in which the cargo is stowed.
    • Hold To accept, as an opinion; to be the adherent of, openly or privately; to persist in, as a purpose; to maintain; to sustain. "Stand fast and hold the traditions which ye have been taught.""But still he held his purpose to depart."
    • Hold To bear, carry, or manage; as he holds himself erect; he holds his head high. "Let him hold his fingers thus."
    • Hold To cause to remain in a given situation, position, or relation, within certain limits, or the like; to prevent from falling or escaping; to sustain; to restrain; to keep in the grasp; to retain. "The loops held one curtain to another.""Thy right hand shall hold me.""They all hold swords, being expert in war.""In vain he seeks, that having can not hold .""France, thou mayst hold a serpent by the tongue, . . . A fasting tiger safer by the tooth,
      Than keep in peace that hand which thou dost hold ."
    • Hold To consider; to regard; to esteem; to account; to think; to judge. "I hold him but a fool.""I shall never hold that man my friend.""The Lord will not hold him guiltless that taketh his name in vain."
    • Hold To derive right or title; -- generally with of.
    • Hold To have; to possess; to be in possession of; to occupy; to derive title to; as, to hold office. "This noble merchant held a noble house.""Of him to hold his seigniory for a yearly tribute.""And now the strand, and now the plain, they held ."
    • Hold To impose restraint upon; to limit in motion or action; to bind legally or morally; to confine; to restrain. "We can not hold mortality's strong hand.""Death! what do'st? O, hold thy blow.""He had not sufficient judgment and self-command to hold his tongue."
    • Hold To maintain in being or action; to carry on; to prosecute, as a course of conduct or an argument; to continue; to sustain. "Hold not thy peace, and be not still.""Seedtime and harvest, heat and hoary frost,
      Shall hold their course."
    • Hold To prosecute, have, take, or join in, as something which is the result of united action; as to, hold a meeting, a festival, a session, etc.; hence, to direct and bring about officially; to conduct or preside at; as, the general held a council of war; a judge holds a court; a clergyman holds a service. "I would hold more talk with thee."
    • Hold To receive and retain; to contain as a vessel; as, this pail holds milk; hence, to be able to receive and retain; to have capacity or containing power for. "Broken cisterns that can hold no water.""One sees more devils than vast hell can hold ."
    • Hold To restrain one's self; to refrain.
    • Hold To retain in one's keeping; to maintain possession of, or authority over; not to give up or relinquish; to keep; to defend. "We mean to hold what anciently we claim
      Of deity or empire."
    • ***
Century Dictionary and Cyclopedia
  • Interesting fact: The stomach of an adult can hold 1.5 liters of material
    • hold To keep fast or close, as in the grasp of the hand; control or prevent the movement or action of, by grasping, binding, arresting, or other means of constraint or detention; retain; keep: as, to hold a horse by the bridle; to hold a prisoner in chains; to hold the attention of an audience; to hold one's self in readiness.
    • hold To keep back; detain: as, goods held for the payment of duties.
    • hold To keep back from action; restrain from action or manifestation; withhold; restrain; check.
    • hold To contain, or be capable of containing; have capacity or accommodation for: as, a basket holding two bushels; the church holds two thousand people.
    • hold To pursue, prosecute, or carry on; entertain; employ; sustain: as, to hold one's course; to hold a court or a meeting; to hold an argument; to hold intercourse.
    • hold Specifically, in music: To sing or play, as one of several parts in a harmony: as, to hold the tenor in a glee.
    • hold To maintain in one part, as a tone, while the other parts progress; dwell upon.
    • hold To have and retain as one's own; be vested with title to; own: as, to hold a mortgage.
    • hold To have or be in possession of; occupy: as, to hold land adversely; to hold office.
    • hold To maintain; uphold; defend: as, to hold one's own; to hold one's right against all comers.
    • hold To entertain in the mind; regard, or regard as; consider, deem, esteem, or judge to be: as, to hold an opinion or a prejudice; to hold one's self free to act.
    • hold To decide; lay down the law: as, the court held that the plaintiff was entitled to recover.
    • hold To bear; endure.
    • hold To support; maintain; keep up; bear; carry.
    • hold To keep or set apart as belonging to some one; keep.
    • hold To bet; wager.
    • hold To continue to resist or endure.
    • hold Said of a tone in music whose duration extends over from one measure to the next.
    • hold To sustain; keep from falling or sinking; hence, to support; uphold.
    • hold To forcibly stop and rob on the highway: as, to hold up a stage or a mail-carrier.
    • hold To be sound or consistent throughout; not to be leaky or untenable: as, the argument does not hold water.
    • hold To keep or maintain a grasp or connection, literally or figuratively; adhere; cling; be or remain unbroken or undetached; not to give way: as, hold on by a rope; the anchor holds well; he holds to his agreement.
    • hold To maintain a position or a condition; stand fast; remain; continue; last: as, hold still; the garrison held out; my promise holds good.
    • hold To hold one's way; keep going on; go forward; proceed.
    • hold To be restrained; refrain; cease or pause in doing something: commonly used in the imperative.
    • hold To have a possession, right, or privilege; derive title: followed by of, from, or under: as, to hold directly of or from the crown; tenants holding under long leases.
    • hold In shooting, to take aim.
    • hold To continue; keep going.
    • hold To stop; halt: chiefly in the imperative.
    • hold To aim directly at moving game.
    • hold To stop; cease; especially, to stop raining.
    • hold To continue the same speed; keep up the pace: a word of command to hunting-dogs.
    • hold In sporting, to maintain one's record, score, performance, or winnings.
    • n hold The act of holding; a grasp, grip, or clutch; a seizure or taking possession; hence, controlling force: as, to take hold; to lay hold of; to keep hold of a thing; imagination has a strong hold upon him.
    • n hold Something which may be grasped for support; that which supports; support.
    • n hold Confinement; imprisonment; keeping.
    • n hold A fortified place; a place of security; a castle; a stronghold.
    • n hold A dwelling; habitation.
    • n hold In law, land in possession; holding; the estate held; tenure: as, freehold, estate held in fee or for life, this being anciently the estate or tenure of a freeman; leasehold, a holding by lease.
    • n hold In musical notation, the sign or , placed over or under a note or rest, indicating a pause, the duration of which depends upon the performer's discretion; a pause or fermata. It is also placed over a bar to indicate either the end of a repeat or a pause between two distinct sections.
    • hold Gracious; friendly; faithful; true.
    • n hold Nautical, the interior of a ship or vessel below the deck, or below the lower deck, in which the stores and freight are stowed.
    • hold Same as hold, intransitive verb, 7.
    • hold To hold or back up (a rivet which is being headed over).
    • hold Specifically, in archery, to make a short pause, after drawing a bow, for fixing the aim and preparing to loose the bowstring.
    • hold Of a female animal, to retain the spermatozoa of the male so that she may become pregnant.
    • n hold In old Eng. hist., the title of an officer in the Danelaw corresponding to the high reeve among the English.
    • ***
Chambers's Twentieth Century Dictionary
  • Interesting fact: The trunk of an elephant can hold up to two gallons of water
    • v.t Hold hōld to keep possession of or authority over: to sustain: to defend: to maintain, support: to occupy: to derive title to: to bind: to confine: to restrain: to stop, as in 'to cry hold:' to continue: to persist in: to contain: to celebrate: to esteem: :
    • v.i Hold to remain fixed: to be true or unfailing: to continue unbroken or unsubdued: to adhere: to derive right:—pr.p. hōld′ing; pa.t. held; pa.p. held (obs. hōld′en)
    • n Hold act or manner of holding: seizure: power of seizing: something for support: a place of confinement: custody: a fortified place:
    • n Hold hōld the interior cavity of a ship between the floor and the lower deck, used for the cargo.
    • v.t Hold hōld (Shak.) to endure
    • v.t Hold hōld (arch.) to bet
    • n Hold (mus.) a mark over a rest or note, indicating that it is to be prolonged
    • ***

Quotations

  • William Shakespeare
    William%20Shakespeare
    “It is not in the stars to hold our destiny but in ourselves; we are underlings.”
  • George Bernard Shaw
    George%20Bernard%20Shaw
    “The only service a friend can really render is to keep up your courage by holding up to you a mirror in which you can see a noble image of yourself.”
  • Jessie B. Fremont
    Jessie B. Fremont
    “Unexplained joy is always so keen that... it seems to hold enough to reconcile one to the inevitable.”
  • Confucius
    Confucius
    “Learn as though you would never be able to master it; hold it as though you would be in fear of losing it.”
  • Raymond B. Fosdick
    Raymond B. Fosdick
    “It is always the minorities that hold the key of progress.”
  • Alexander Pope
    Alexander%20Pope
    “An obstinate person does not hold opinions; they hold them.”

Idioms

Can't hold a candle - If something can't hold a candle to something else, it is much worse.
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Don't hold your breath - If you are told not to hold your breath, it means that you shouldn't have high expectations about something.
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Hold all the aces - If you hold all the aces, you have all the advantages and your opponents or rivals are in a weak position.
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Hold the baby - (UK) If someone is responsible for something, they are holding the baby.
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Hold the bag - (USA) If someone is responsible for something, they are holding the bag.
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Hold the fort - If you hold the fort, you look after something or assume someone's responsibilities while they are away.
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Hold the torch - If you hold the torch for someone, you have an unrequited or unspoken love.
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Hold the wire - If you ask someone on the telephone to hold the wire, you want them to wait and not hang up.
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Hold water - When you say that something does or does not 'hold water', it means that the point of view or argument put forward is or is not sound, strong or logical. For e.g., 'Saying we should increase our interest rates because everyone else is doing so will not hold water'.
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Hold your hands up - (UK) If you hold your hands up, you accept responsibility for something you have done wrong.
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Hold your horses - If someone tells you to hold your horses, you are doing something too fast and they would like you to slow down.
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Hold your own - If you can hold your own, you can compete or perform equally with other people.
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Hold your tongue - If you hold your tongue, you keep silent even though you want to speak.
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No holds barred - If there are no holds barred, there are no rules of conduct; you can do anything.
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On hold - If something is on hold, no action is being taken.
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Etymology

Webster's Revised Unabridged Dictionary
OE. haldan, D. houden, OHG. hoten, Icel. halda, Dan. holde, Sw. hålla, Goth,. haldan, to feed, tend (the cattle); of unknown origin. Gf. Avast Halt Hod

Usage

In literature:

And they already had one minor victory to taste sweet: Mount Sterling had fallen into their hold as easily as it had before.
"Ride Proud, Rebel!" by Andre Alice Norton
And, look you, when you've got hold, don't you leave hold.
"The History of Sir Richard Calmady" by Lucas Malet
The goods assume the shape of the wooden "form," and will always hold it if the work has been carefully and thoroughly done.
"Textiles" by William H. Dooley
What he saw there rooted him to his chair, holding him spellbound.
"The Rich Little Poor Boy" by Eleanor Gates
His proposition simply did not hold water.
"The Snowshoe Trail" by Edison Marshall
They will pour it slowly and hold the glass up against the light and admire its color!
"Blow The Man Down" by Holman Day
They stand in a long line or rank side by side, holding hands.
"Games for the Playground, Home, School and Gymnasium" by Jessie H. Bancroft
The voyageurs first get out and wade to the shore, one or two remaining to hold the canoe in its place.
"Popular Adventure Tales" by Mayne Reid
She asked herself why she had not obeyed the profounder instinct that had urged her to hold him as long as she had the power to hold?
"The Creators" by May Sinclair
He used all his knowledge now, trying the shoulder hold and the waist hold and to trip, but every attempt failed.
"The Riflemen of the Ohio" by Joseph A. Altsheler
The situation of casks when they are stowed in the hold athwart ship, or in a line with the beam.
"The Sailor's Word-Book" by William Henry Smyth
No scruples would hold him back from the possession of his desires.
"The Fighting Edge" by William MacLeod Raine
We'll lock the door and I'll hold them here long as I can.
"Crooked Trails and Straight" by William MacLeod Raine
First of all his mother took hold of him by the flaxen hair, and pulled it.
"Jewish Children" by Sholem Naumovich Rabinovich
Hold the audacious one!
"The Wagnerian Romances" by Gertrude Hall
Asher Aydelot sat on the wagon seat holding the reins.
"Winning the Wilderness" by Margaret Hill McCarter
Is it anything a fellow can take hold of and hold on to?
"The End of a Coil" by Susan Warner
You do not know where to hold the glass or where to hold the pitcher.
"Common Science" by Carleton W. Washburne
I'll hold her an extra hour or two if you would like to go.
"Astounding Stories of Super-Science, June, 1930" by Various
OFFICE HOLDING: Women are not forbidden by law to hold any office except that of legislator.
"The History of Woman Suffrage, Volume IV" by Various
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In poetry:

Sometimes a joy lays hold on me,
And I am speechless then;
Almost a martyr I could be,
To join the holy men.
"The Disciple" by George MacDonald
You hold me in your arms.
How strange that you're so tender!
Child-woman that I am,
you think that you can mend her.
"Cripples And Other Stories" by Anne Sexton
But still my human hands are weak
To hold your iron creeds:
Against the words ye bid me speak
My heart within me pleads.
"The Eternal Goodness" by John Greenleaf Whittier
Lady of the surplus skirts,
Do not hold that pose. It hurts.
Tell us, what is your intent
Toward that distant Parliament?
"Lines to a Canberra Stamp" by C J Dennis
Each tiniest plant that blossoms
With the perfume of its birth
Holds in its cup the secret
Of the whole mysterious earth.
"Autumn Days" by Franz Emanuel August Von Geibel
"He was there alone," when even
Had round earth its mantle thrown,
Holding intercourse with heaven:
"He was there alone."
"Solitude" by John Bowring

In news:

The Port-O-Rotary, which comes in red or black, holds a secret — and no, it does not turn on a signal in the Batcave.
It is a basic axiom of cinema that kids and animals are to be dealt with kindly if a character wants to hold onto an audience's sympathy.
And with these voters likely to hold stronger, and more consistent, views on abortion, the fight between pro-life and pro-choice activists is likely to continue despite the ambivalence felt among most Americans.
House Oversight and Government Reform Committee chairman Darrell Issa issued a memorandum and draft contempt report on Thursday making the case for holding Attorney General Eric Holder in contempt of Congress.
Quadski holds one person with the ability to do 45 mph on land, water.
GOP House committee holds Attorney General Holder in contempt.
The collections inside this museum hold intriguing objects that tell the story of 19th century American medicine.
Do some of today's languages still hold a whisper of the ancient mother tongue spoken by the first modern humans.
Stop holding debt ceiling hostage.
New data may hold the answer.
Zacks Bull and Bear of the Day Highlights: RenaissanceRe Holdings, Ryder System, Nobl.
What is holding PAT back.
Bolt 's holds the world record in both disciplines and holds six Olympic gold medals, after also winning the men's 4x100m relay in 2008.
Tucson News NowRDA Holding Co. To Hold Third Quarter 2012 Financial Call on Tuesday.
Holding his daughter Caroline, US Senate candidate Ted Cruz and and his wife, Heidi, holding their daughter, Catherine, appear before a cheerful crowd after Cruz defeated Republican rival, Lt Gov.
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In science:

Moreover, noninteraction holds: NI Pl(X = i; X = j ) holds for i; j  fh; tg.
Conditional Plausibility Measures and Bayesian Networks
Then Proposition 9.8 holds for L/K if and only if it holds for E /K .
Ramification of local fields with imperfect residue fields
In order to prove that (11) holds for minv π(v) ≤ x ≤ 1/2, it suffices to prove that it holds for minv π(v) ≤ x ≤ q for some constant q , as the function ϕ is decreasing.
On the mixing time of simple random walk on the super critical percolation cluster
When Ji resolves, this condition holds, and when the condition holds Ji+1 resolves.
On Resolving Singularities
We note that equation (5) holds for some x if and only if it holds for any vertex of X .
Classification on the average of random walks
Since the function fǫ has a polynomial growth at infinity, therefore there exist even polynomials S (r) and Q(r) such that S (r) ≤ fǫ (r) ≤ Q(r) holds for every r ≥ 0 and furthermore |S (r) − fǫ (r)| < ǫ, |Q(r) − fǫ(r)| < ǫ hold for every 0 ≤ r ≤ kxtk.
Random regularization of Brown spectral measure
In above discussions, we have proved that, if we suppose that when L = N eq.(11.196) holds, then it also holds when L = N + 1.
Gauge Theory of Gravity
Since X ⊂ XQ it follows that, if (iii) holds then (iv) holds.
Classification of unipotent representations of simple p-adic groups,II
Clearly, if (a) holds for V then it also holds for V ⊗n for any n ≥ 0.
Classification of unipotent representations of simple p-adic groups,II
As we have seen earlier, (a) holds for V ⊗n hence it holds for V .
Classification of unipotent representations of simple p-adic groups,II
Indeed, it is clear that if (b) holds then (c) holds.
Classification of unipotent representations of simple p-adic groups,II
Left Registeri |Right Registeri , the left intended to hold the arguments x of eϕ, the right to hold the corresponding values of eϕ.
Quantum Hidden Subgroup Problems: A Mathematical Perspective
More precisely, p(u, v , p(x, y , z )) = p(p(u, v , x), y , z ) holds if uRv , yS z , and either vS x or xRy , while p(x, y , z ) = p(z , y , x) holds for any xRyS z .
Linear extensions and nilpotence for Maltsev theories
Pf ∈G Pr(Y = f −1g) = maxh∈G Pr(X = h). A similar argument holds for minh∈G Pr(Y = h) and maxh∈G Pr(Y = h). 2 Lemma 2.6 (Babai and Szemer´edi [BS84]) The fol lowing holds: g /∈ A−1A ⇔ Ag ∩ A =
Towards a practical, theoretically sound algorithm for random generation in finite groups
This fact leads to the conclusion that IM presents integral of motion if we choose the substantial volume in such a way that initial volume eV |t=t0 is such that Hn |t=t0 = 0 because this condition is invariant of the motion: if equality Hn = 0 holds for the initial moment then it holds true in the future.
Canonical description of ideal magnetohydrodynamics and integrals of motion
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